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Perinatal factors and handedness in twins at six and one-half years Giles, Lucille Dorrean 1980

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PERINATAL FACTORS AND HANDEDNESS IN TWINS AT SIX AND ONE-HALF YEARS by LUCILLE DORREAN GILES B.A., University of British Columbia, 1975 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ARTS in THE FACULTY OF GRADUATE STUDIES (Department of Psychology) We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA May, 1980 (c) Lucille Dorrean Giles, 1980 In p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t o f the r e q u i r e m e n t s f o r an advanced degree a t the U n i v e r s i t y o f B r i t i s h C o l u m b i a , I agree t h a t the L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and s t u d y . I f u r t h e r agree t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y purposes may be g r a n t e d by the Head o f my Department o r by h i s r e p r e s e n t a t i v e s . I t i s u n d e r s t o o d t h a t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l not be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . Psychology Department o f The U n i v e r s i t y o f B r i t i s h Columbia 2075 Wesbrook P l a c e Vancouver, Canada V6T 1W5 D a t e May 20, 1980 Abstract The purpose of this study was to examine the relationship between perinatal factors and handedness in twins at six and one-half years. Longitudinal data concerning 66 twins from the U.B.C. Department of Pediatrics Premature's Growth and Development Survey were used to determine specific prenatal, postnatal and neurological indicators of non right-handedness . Analysis of the data indicated that four perinatal high risk factors were the maternal complications of toxemia, diabetes, age and medications. Discriminant functions on six perinatal high risk categories revealed that Mother's Perinatal Problems, Infant's Breathing Problems and Infant's Neurological Status were significantly related to non right-handedness. Both the limitations and implications of the findings were discussed. i i i Table of Contents Page Abstract i i Table of Contents i i i List of Tables iv Acknowledgement v I. Introduction 1 II. Method 33 Subjects 33 Materials 34 Procedure 35 III. Results 38 IV. Discussion 41 References 50 Appendix A: UBC Prenatal Record - 66 Appendix B: UBC Labour and Delivery Record 75 Appendix C: UBC Nursery History Record 81 Appendix D: UBC Neonatal Examination 87 Appendix E: UBC Neonatal Neurological Examination . . . . 93 Appendix F: UBC Handedness Test . 103 iv. List of Tables Page Table 1 Phi coefficients for perinatal risk factors and handedness 39 Table 2 Percentages for perinatal profiles in non right-handers 40 -Table 3 Discriminant function weights and group means for risk categories by handedness 42 Acknowledgement v I wish to express sincere gratitude to my committee members, Dr. Michael Chandler, Dr. Ralph Hakstian and Dr. Larry Walker, as well as to other caring faculty, Dr. Tamils- Williams, Ms. Nancy Horsman, Dr. David Williams and Dr. Lou Moran. Appreciation is also extended to enduring friends, Betti and Rori Clipsham and Patricia Williams. Special thoughts go to my parents, Lorna and Herbert Conner, and the dedication of this thesis to my husband and sons, Harold, Gordon, Jimmy, Randy and Stephen. I. Introduction 1 The purpose of this research was to examine perinatal contributions to handedness. To accommodate this, sixty-six twins were studied, with comparisons being made between their condition at birth, and handedness at six and one-half years. While this is not an attempt to arbitrate the question of possible genetic contributions, the decision was made to study twins for the following reasons: twins create a high-risk population in that compared to singletons, they evidence more perinatal problems as well as a higher proportion of non right-handedness. Working with a high-risk group allowed the reasonable expectation that discernible differences between right-handers and non right-handers might occur. Also, data concerning conditions of twins during gestation,delivery and the postnatal period, and their handedness at six and one-half years was available from a propsective survey of low birth weight children (Crichton, Dunn, McBurney, Robertson & Tredger, 1972) . This presented a valuable opportunity to investigate the relationship between perinatal factors and handedness. The following thesis explores this topic. Handedness is one aspect of cerebral dominance. Cerebral dominance refers to the concept that one hemisphere of the brain is dominant over the other for most functions. This dominance is said to be exhibited in an individual by his lateral strength and consistency in the use of various parts" of his body. Strong right dominance is inferred i f an individual uses his right eye. right ear, right hand and right foot instead of their counterparts for most of his actions; while strong left dominance is indicated i f the reverse is true. Mixed dominance may exist i f an individual uses one side of his body variably, e.g. right eye, left hand and right foot. Specific aspects of dominance are also identified. If an individual uses his left hand for approximately five out of ten actions and his right for others, he is said to be exhibiting variable or mixed handedness. If he uses 2 his right hand for a specific action one time, but uses his left at another, his handedness may be considered inconsistent. If for a l l actions, each hand is used equally well, he would be termed ambidextrous. Methods of assessing handedness include tested preference (e.g. Hand Preferences; Harris, 1958), tested s k i l l (e.g. Grooved Pegboard Test; Klove, 1963), tested strength (e.g. Koch, 1933), and self-report (e.g. Edinburgh Inventions, Oldfield, 1971). Several handedness skills have been studied. Most individuals show a superiority for the use of the preferred hand (usually right) while there is at least some contribution of fine motor control to the task. However, there appear to be no differences between handedness groups in the speed or legibil-ity of writing (Reed & Smith, 1962) or in tracking accuracy. Preference asymmetry between the hands has been shown in investigations where timing or serial organisation is important (e.g. Provins & Cunliffe, 1956) . Provins (1972) showed that the potential s k i l l level of the nonpreferred hand is as high as that of the preferred. Oldfield (1969) considered handedness to be related to the expression of intention and volitional control. Barnsley and Rabinovitch (1970) found the preferred hand to be superior in terms of a variety of sensory and performance measures. In the relation of handedness to reaction time, responses with the preferred hand appear to be faster, but other factors, e.g. the nature of the response demanded, its compatibility with other aspects of the task and its position in the sequence of responses, are of greater importance. With respect to simultaneous responses with the hands, there is no tendency for one hand to lead the other, but there are lateral difference in the perception of simul-taniety (Efron, 1963, a,b.). The importance of the hand employed in a simple 3 response in relation to the visual field of stimulation has also been shown (Umilta, Frost & Human, 1972). Cerebral dominance was recognized at least as early as 3,000 B.C. (Cadwallader, Semrau and Cadwallader, 1971) although there were few investiga-tions until the middle of the last century. In 1648, Browne discussed a "prevalency" which, was thought to arise at either side of the brain and related this to bodily control. Bouillard, in 1830 suggested that the "leading" hemisphere was associated with handedness. Jackson (1874) identified propositional speech with the left hemisphere. Detailed analysis of the functional specializations of the two cerebral hemispheres appears to have originated in 1836 with the work on aphasia, when Dax, after observing brain-damaged individuals, postulated that aphasia was related to left-sided lesions of the brain. Broca (1865), having previously held that both hemispheres were concerned with speech, claimed, on the basis of eight consecutive cases of aphasia, that the left hemisphere was dominant for this function. In 1874, Wernicke specified areas of the left hemisphere where damage was the cause of both auditory comprehension loss and different language disorders. Dejerine (.1891) showed that the loss of reading comprehension and writing skills often depended on a left unilateral lesion. Jackson (1932) elaborated the concept of a dominant hemisphere. Assuming speech to the highest function which man has the capacity to perform, he reasoned that since damage to one particular hemisphere could destroy the capacity for speech, this hemisphere must exercise control. The non-dominant hemisphere supposedly behaved in an automatic or involuntary fashion. In agreement was Brain, who in 1945 stated, "motor integration seems to require 4 that the motor cortex of both hemispheres should be under the control of a single co-ordinating area, "the motor speech centre." " Although these investigations were based on the left hemisphere right hand association, other findings (Branch, Milner & Rasmussen, 1964) appeared to support the concept of the left hemispheric dominance by demonstrating that, regardless of peripheral lateral preferences (usually hand), the speech of most individuals seemed to be mediated by the left cerebral hemisphere. These views led to theoretical positions which suggested an advantage in strong or consistent lateral preferences in strengthening hemispheric functions. In at least one instance (Delacato, 1959) childhood training towards unilater-a l ! ty was looked upon as being "favourable" and as "hurrying the evolutionary process." Alternate views of lateralization of hemispheric functions have been proposed: a) both hemispheres are equal at a l l times (Chesher, 1936); b) either hemisphere may be dominant at one time, depending upon the required function (Zangwill, 1960); c) no hemisphere is dominant at any time — only specific functions are dominant (Dimond, 1971) . The work of Sperry (1964) and others may be viewed as lending support to the latter theories. Sperry, after studying operations which severed the corpus callosum in animals, concluded that animals were endowed with two independently functioning "brains". Each "brain" was found to be comparable to the whole brain in the solving of a given problem. Gazzaniga (1967) investigated humans who, for medical reasons, (e.g. epilepsy) had undergone the brain-splitting operation. He found that in humans, as in Sperry's animals, there also appeared to be "two brains," each separately capable of higher order mental functions. Gazzaniga therefore 5 suggested that the corpus callosum of the intact brain combined and integrated the functions of both hemispheres creating two independent spheres of consciousness within a single cranium, i.e. within a single orgainism. He also speculated that in children up to the age of four, the right hemisphere may be as proficient as the left with regard to language and speech functions. Results from split-brain studies have thus placed in question the concept of left hemispheric dominance for a l l functions. In addition, the finding that language functions are represented in both hemispheres undermines the foundations of the traditional concept. Other studies have more closely investigated the specific functions of each hemisphere. Some functions typically localized more in the left hemisphere are linguistic (e.g. Wiesenberg and Mcbride, 1935), symbolic and propositional (e.g. Humphrey and Zangwill, 1952)^.verbal (e.g. Milner, 1958), logical and analytic (e.g. Levy-Agresti & Sperry, 1968), and discrete (Semmes, Weinstein, Ghent & Teuber, 1960). There is also evidence for right hemispheric dominance in areas such as perception of colors (Scotti and Spinnleo, 1970), photographs (Benton & Allen, 1968), drawings of objects (DeRenzi, Scott and Spinnler, 1969), drawings of scenes (Ettlinger, 1960), enumerations (Kimura, 1966), dot localization (Kimura,1969), stereopsis (Durnford & Kimura, 1971), vigilance tasks (Dimond & Beaumont, 1971), facial recognition (Gilbert & Bakan, 1973), relations (Boll, 1974), tactile perceptions (Benton, & Van Allen, 1968) and emotions (Dimond, & Farrington & Johnson, 1976) . Depending upon type of subject area of dominance, method of testing, etc., different lateralty effects are often obtained. For example, different types of emotions have been ascribed to both right and left hemispheres. Gainotti (1972) compared the emotional reactions of eight left 6 hemisphere-damaged and eight right-hemisphere damaged patients and showed that behaviours i n d i c a t i n g an anxious-depressive o r i e n t a t i o n of mood (anxiety reactions, bursts of tears, vocative utterances, depressive renouncements) were found to be s i g n i f i c a n t l y more frequent among left-hemisphere damaged pa t i e n t s . By contrast, symptoms denoting a minimum of opposite emotional reactions (as w e l l as i n d i f f e r e n c e reactions and a tendency to joke) and expressions of hate toward the paralyzed limbs, were found to be s i g n i f i c a n t l y more frequent among r i g h t hemisphere-damaged p a t i e n t s . G a i n o t t i o f f e r e d the following explanations; the l e f t hemisphere-damaged patients could not e f f e c t i v e l y perform, and thus appeared to react desparately to a task they could not face, while i n the right-hemisphere-damaged p a t i e n t s , the i n d i f f e r e n t reactions and behaviours of neglect were considered to be caused by the d i s o r g a n i z a t i o n of the "non-verbal" type of synthesis of the sensory data which i s supposed to be c h a r a c t e r i s t i c of the r i g h t hemisphere. I t i s now generally accepted that, depending on which functions are c a l l e d upon by the demands of performance, d i f f e r e n t hemispheres are dominant at d i f f e r e n t times. This "partnership" hypothesis i s described by Dimond (1971): "The language functions of right-handed people r e l a t e predominately to the l e f t hemisphere, and v i s u o - s p a t i a l functions to the r i g h t hemisphere. Writing with the r i g h t hand employs the functions of the l e f t hemisphere and drawing employs the functions of the r i g h t hemisphere. I f v i s u o - s p a t i a l functions are to be a v a i l a b l e to the r i g h t hand for use i n drawing, then responses are i n s t i g a t e d not by the l e f t (the dominant hemisphere), but by the r i g h t (the non-dominant), e s t a b l i s h i n g i t s i n f l u e n c e throughout the corpus callosum." A s i m i l a r model has been proposed by Semmes (1968) and developed by Satz and Sparrow (1970) . Semmes suggests that f o c a l representation i s found i n the l e f t hemisphere, while that i n the r i g h t i s d i f f u s e . Such a struc t u r e favours the i n t e g r a t i o n of s i m i l a r units w i t h i n the l e f t hemisphere, 7 especially for fine sensory-motor control (e.g. as in manual operations or in speech). The right hemisphere would be better at multimodal, and therefore spatial, operations, Satz and Sparrow (1970) elaborating on Semmes' work, proposed a model of hierarchial levels in hemispheric specialization. They suggested that the lateralization of motor function, somato-sensory function, and of speech and language form different analytic levels, each in the form that Semmes had proposed. Research in cerebral dominance has been stiumlated mostly because of practical problems encountered with brain-damaged individuals, e.g. i f the left hemisphere is damaged, might speech and language functions be trained via the right hemisphere? Or, i f through damage to either hemisphere, use of a dominant limb becomes impaired, might there be a possiblity of transfer of sk i l l to the opposite side of the body? Educators often question handedness irregularities in primary-school students (McWhirter, 1976) e.g. is i t possible for non right-handers to switch their handedness and improve their writing skills? If so, will such students suffer irreparable speech or emotional problems? Handedness has also been of particular clinical concern because of reported associations between non right-handedness and such problems as aphasia (Levy, 1969), epilipsy and mental retardation (Bingley, 1958), low achievement and low I.Q. scores (Koos, 1964), reading disabilities (Marcel, Katz & Smith, 1974), poor perceptual motor functioning (Denckla, 1974), stuttering (Palmer, 1964), learning disabilities (Critchley, 1970), alcoholism (Bakan, 1973), autism (Colby & Parkinson, 1977), schizophrenia (Lishman & McMeekan, 1976) and negative personality traits (Blau, 1946) . Large scale studies (Bakwin, 1950; Karpinos & Grossman, 1953; Chateau, 1962) indicate that in western society between 5% and 12% of the population are non 8 right-handed. There are more males than females in this group (e.g. Burt, 1921; Hecaen & Ajuriaguerra, 1964; Kaufman, 1975). Cross cultural studies (e.g. Teng, Lee, Yang & Chang, 1976) suggest these patterns of manual preference are typical. Historical records indicate that man has been right-handed for many centuries (e.g. Coren & Porac, 1977) but that strong right dominance may be a relatively recent evolutionary development (Parello, 1970). Developmental studies are unclear as to the age at which handedness emerges. Most results (e.g. Belmont & Birch, 1963; Gessell & Ames, 1947) show hand dominance to follow an irregular pattern, appearing at age five, subsequently becoming confused and reappearing at age nine. However, Bresson, Maury, Pierant-le Bonniec & De Schonen (1977) in a study of infants ranging from 17-40 weeks old, reported that from 22 weeks onward, the right hand was most skilled in reaching for objects. Caplan & Kinsbourne (1976) indicated that infants of approximately 10 weeks maintain grasp of a rattle for a longer time with the right than the left hand. Coryell (1977) considered head position and the asymmetrical tonic neck reflex (ATNR) to be a contribution to the develop-ment of handedness. In a study of one to 12 week old infants i t was found that most l i e supine with their heads to the right. The head right posture elicits an ATNR which places the infants' right hands within their visual fields more frequently. This increased visual experience with the right hand appears to lead to greater activation of the right hand when the infant is looking at a stimulus object. / Attempts to provide an explanatory basis for handedness have called upon a wide variety of factors. Investigations of eyedness (e.g. Porac & Coren, 1975) have generally failed to confirm a relationship between i t and handedness. Footedness and handedness appear to be correlated (Higginbottam, 1973) as does earedness and handedness. Dichotic listening investigations (e.g. Hynd, 9 Obrzut, Weed & Hynd, 1979) generally indicate right-ear (i.e. left-hemisphere) right-hand associations. Somatosensory studies indicate a greater sensitivity for tactual and related thresholds on the preferred side (Cannon, Bilstrom & Benton, 1969). There are also reports of lateral differences in galvanic skin response. E.g. Khoruzhaia (1962) reports an increase in skin temperature of the temporal area corresponding to the dominant hand while the subject reads or solves an arithmetic problem. Positive and negative reports of electrophysiological (e.g. E.E.G.) correlates of handedness are also reported (see review Giannitrapani, 1967) . The algebraic comparison of the percentage of leading activity in parietal and occipital areas has been suggested to be associated with direction and degree of manual preference in adults (Provins & Cunliffe, 1972) . Organ asymmetry investigations have shown correlates between brain structure and handedness. Results generally show (e.g. Lemay & Geschwind, 1975) brains without a particular asymmetry are more common in the left-handed; i.e. the left-handed are more likely than the right-handed to show the reverse asymmetry, but the extent of the asymmetry is less striking. In some cases the asymmetry is in the same direction in the left-handed as in the right-handed, but again is less striking in magnitude. Asymmetries appear to be inborn, since they are present in the fetus. Sex differences in the distribution and extent of asymmetries are also suggested (Hardyck and Petrinovich, 1978; Wada et al, 1975). The left side of the brain appears to be better vascularized (Carmon & Gombos; 1970) which may promote right-handedness. There is controversy as to whether these asymmetries are of functional importance (Von Bonin, 1962) . It is possible that the functions of large areas usually found 10 on the right side of the brain are different from functions of very large areas usually found on the lef t . For example, a larger left than right planum temporale might indicate a significant degree of verbal ability, while a larger right than left planum may signify a high degree of musical potential (Hardyk & Petrinovich, 1977). An alternative speculation is that homologous areas have similar functions; and a larger area on one side would indicate that that side is dominant for a function (Geschwind & Levitsky, 1968). Social evolution theories also offer explanations for handedness. The most common theory is the "sword and shield", which has had numerous advocates (Gould, 1908; Harman; 1905; Pye-Smith, 1871; Woodruff, 1909). The basic argument is that the soldier who held his shield in his left hand offered his heart better protection and thus had a better chance of survival. By the same process, his right hand grew more skilled in manipulative movement and eventually came to be used for a l l skilled manipulative activities. Salk (1966) used a social evolution theory to explain the lower incidence of left-handedness in women. He suggested that human infants are imprinted by the sound of the mother's heartbeat in utero and, as commonly found with imprinted stimuli, seem to exhibit a relative freedom from anxiety in the presence of the stimulus. Mothers, both right and left-handed, also hold their newborn infants on their left side to an extent of approximately 80% (Salk, 1962; Weiland, 1964). It is suggested that the soothing effect of the mother's heartbeat is advantageous to the health and survival of the child. This habit of carrying the baby on the left gives the right-handed mothers and their children an advantage. Presumably in the absence of a genetic or culture component, random learning would habituate a person to use right or left (Collins, 1968, 1969, 1970, 1975) because consistent use of one hand over the other makes one more adept. In early hominid evolution when tool use and 11 manual efficiency became predominant models of adaption, there probably arose strong selective pressures for mothers who tended to bear their infants in the left arm, thus freeing the right hand to perform increasingly complex tasks. Paredes & Hepburn (1975) suggested that differing types of cognition in various cultures are the basis of lateral differences. "Primitive" and "civilized" cognitive processes are correlated with the right and left hemispheres respectively. That is, cognition proceeding from the right hemisphere is seen as being synthetic, analogical, and concrete, while that of the left hemisphere is seen as being analytic, digital and abstract. Different cultures may use one hemisphere more extensively than the other and therefore evidence different types of handedness. Martindale (1976) questions whether "primitive" mentality actually exists and whether i t is based on physiological variables. Subculture differences in the cognitive mode have also been examined. Cohen (1969) and Lesser (1971) found that in the United States the middle class are more likely to use a verbal-analytic mode whereas the lower class are more likely to use a spatial-holistic mode. From these results i t is postulated (Galin, 1976) that there may be a cultural conflict of cognitive styles which could explain the difficulties of lower class children in a school system oriented toward the middle class. Dawson (1974) investigated a conformity factor in various cultures and reports on societies with varying degress of permissiveness toward left-handed-ness. He shows averages of 10.4% for societies he characterized as "extremely permissive," 5% for "permissive" and 1.8% for "harsh, restrictive" societies. 12 Anthropological evidence (Hertz, 1909) from the Maori, Polynesians and Australian Aborigines suggest that belief systems are linked to handedness. In these cultures the right hand is often regarded as sacred and associated with the male whereas the left hand is thought of as feminine and profane. Barsley (1966) argues that the cultural norms favoring the right hand are further reinforced through socialization where the left hand is regarded as the unclean hand, while the right is reserved for shaking hands and saluting. Religious influences are suggested by Robinson (1977) who reports that Catholics are urged to make the sign of the cross fight-handed and are often referred to as "right-handers". The relationship is strengthened because of the supposed association of left-handedness with evil. This relation is further evidenced by the fact that the English word "sinister" comes from the Latin word for "left". Genetic models for handedness have also been developed. Most argue that left-handedness is carried as a Mendelian recessive trait. The data base for these arguments is far from adequate. Trankell (1950) collected data in support of the genetic model on 1600 seventh-grade children and their parents in the city schools of Stockholm. However, this data from parents were collected by questionnaire, and the unreliability of such data collection for handedness has been shown in several studies (e.g. Benton, Meyers & Polder, 1962; Satz, Achenbach & Fennell, 1967). Falek's study, (1959) which used interviews and behavioral testing to determine incidence and preference, produced inconclusive results. This was possibly due to his disregarding those individuals who had no strong hand preference. Studies suggest (Dee,1971; Hecaen & Sauget, 1971) that those individuals who have a family history of left-handedness are also less likely to be strongly left-handed. By attempting to select clearly defined groups, Falek may have discarded the genetically meaning-13 f u l portion of his data. The ambiguity of many data in this area has been pointed out by Fuller (1960) who noted that the same data have been used both to support and to disprove genetic theories. Most recent genetic models have been those of Annett (1964), 1967, 1972, 1973a, 1973b, 1974, 1975) and Levy & Nagylaki (1972). The Annett model (1972) proposes that there are two components underlying the distribution of human handedness. One is a bell-shaped component, reflecting random or "accidental" influences. The other i s the "right - s h i f t " component, which Annett assumes to be genetic, and which accounts for the fact that most people are right-handed. It might perhaps be questioned whether there i s any variation in the right-shift component, since the random component could presumably override the right-shift i n some small proportion of individuals to produce l e f t -handedness. Annett (1972) suggests, however, that left-handedness might also be attributed partly to a "weak dose" of the right shift. In a later a r t i c l e (Annett, 1974) she suggests, however, that the right-shift may sometimes be completely lacking. A m o n g individuals who lack the right s h i f t , an unbiased test of handedness should reveal equal proportions of right-and left-handers. If this condition is inherited, the children of couples who are left-handed should display no overall superiority with either hand. To test this, Annett studied intermanual differences on a peg-moving task among the offspring of 29 left-handed couples. Among these families there were five i n which one or both parents reported some history of perinatal d i f f i c u l t y or other early stresses which might have influenced their own handedness. The eight children of these couples were significantly faster on the task with their right hands than with their l e f t . However, the 45 children of the remaining 24 couples showed an average intermanual difference that was essentially zero and were about 14 equally divided between those faster with the right hand (23) and those faster with the left (22). As predicted, these children evidently lacked the right-shift component. Annett's (1974) experiment suggests that there is a difference between familial and nonfamilial left-handers. Familial left-handers do not inherit left-handedness per se; rather they inherit the absence on any bias toward either left-or right-handedness or toward any consistent cerebral lateraliza-tion. The nonfamilial group may be left-handed for reasons associated with birth stress or prenatal pathology. If i t is supposed that mild damage to the left hemisphere is more likely to cause a child to switch handedness than to switch speech representation (Satz; 1972, 1973), then i t can be understood why more individuals are left-handed than have speech represented in the right hemisphere (e.g. Goodglass & Quadfasel, 1954). Annett's model (1972), however, does not f i t the data of Hecaen and Sauget (1971) either on strength of handedness or on bilateral speech representation in many left-handed. In her most recent account (1975) Annett reviewed a number of lesion studies with respect to her model, arguing that three of the studies (Bingley, 1958j Newcombe and Ratcliff, 1973; Penfield & Roberts, 1959) were in accordance with the results of her genetic model. The studies of Conrad (cited in Zangwill, 1967) and Hecaen and de Ajuriaguerra 1964), however, show significant discrepancies. Annett's model (1975) also did not take into account the extensive study done by Hecaen and Sauget (1971). Since Hecaen and Sauget took great care to evaluate both preferred handedness and family history of handedness, this is a serious omission. Also, Annett's model requires a lateralization of speech to either the left or the right hemisphere, which requires dismissing the considerable body of both lesion 15 (Branch, Milner, & Rasmussen, 1964; Hecaen & Sauget, 1971; Wada & Rasmussen, 1960) and behavioural (Lomas & Kumura, 1976) evidence f o r b i l a t e r a l speech representation i n many left-handed. The two-gene, f o u r - a l l e l e model presented by Levy and Nagylaki (1972) i s the most d e t a i l e d and comprehensive of the genetic models. It has r e c e n t l y been c r i t i c a l l y evaluated by Hudson (1975) who argued that the model i s unable to account for observed d i s t r i b u t i o n s of handedness i n three sets of data. The Leyy-Nagylaki model does attempt to explain b i l a t e r a l i z a t i o n of function, but argues that only h a l f the population of f a m i l i a l left-handed should show b i l a t e r a i l i t y . In view of the large number of studies reporting that i n t e r -hemispheric d i f f e r e n c e s are l e s s pronounced i n the left-handed, t h i s aspect of the model seems suspect. Perhaps the p r i n c i p l e c r i t i c of the genetic explanation is C o l l i n s (1968, 1969, 1970, 1975), who has argued that handedness can be accounted f o r without any recourse to genetic considerations, a p o s i t i o n strongly contested by proponents of genetic models (Nagylaki & Levy, 1973). Twin studies have provided no c l e a r evidence for a genetic f a c t o r of handedness. D i s t r i b u t i o n s of concordant ( i . e . consistent) and disconcordant handedness among both monozygotic and d i z y g o t i c twins are very c l o s e l y approximated by binomial expectations ( C o r b a l l i s & Beale, 1976). Nagylaki & Levy (1973) protest that twins are not representative of the general population. They give pooled estimates of .145 f o r monozygotic twins, .109 for d i z y g o t i c twins, but only .067 f o r the general population. 16 Collins (1970) provides similar estimates but argues that the higher proportion of left-handedness among twins simply imposes an extra burden on genetic explanations. In reply, Nagylaki and Levy counter that this is evidence for a spurious, nongenetic influence, related to increased pathology among twins. They cite evidence that twins also show a higher frequency of mental deficiency, brain damage and infant mortality than the singly born. Also raised is the question of mirror-imaging effects, which may artifically increase the proportion of monozygotic twins who are discordant for handedness. In cojoined twins, i t is usual to find "situs inversus," with reversal of the heart and other visceral organs (Newman, 1940). However, true "situs inversus" is extremely rare among separate monozygotic twins, perhaps as rare as in the general population (Torgerson, 1950). Yet Newman (1940) observes that monozygotic twins often show reversals in ectodermally derived tissue, which excludes the viscera but includes handprints, hair whorls, handedness, and eye dominance. He suggests that the frequency of mirror-imaged features may depend on how late in development the embryo divides to form twins; in cojoined twins the division begins so late that i t remains uncompleted and the mirror imaging extends even to the viscera. Newman also points out the difficulty in distinguishing special mirror-imaging effects peculiar to monozygotic twinning from more general factors which operate in the population at large to produce occasional reversals (e.g. hairwhorl being in a left direction in one twin and in a right direction in the other twin). He notes that the great majority of twins display no mirror-imaged features. Newman's interpretation is that reversals among twins do not depend on twinning per se, but are simply a consequence of prenatal environmental conditions which may also affect the singly born, although perhaps to a lesser 17 extent. R i f e (.1940) suggests, that environmental pressures, among twins, due to crowding i n the uterus, may w e l l increase the proportion of cases- i n which one twin i s right-handed and the other left-handed. This would presumably apply to d i z y g o t i c as w e l l as to monozygotic twins and could explain c o r r e l a t i o n s which were lower f o r both kinds of twins than f o r paired s i b l i n g s i n general. The f a c t that twins are more l i k e l y than the s i n g l y born to be left-handed r a i s e s the p o s s i b i l i t y of an i n d i r e c t genetic e f f e c t . The d i s p o s i t i o n to conceive twins might i t s e l f be maternally i n h e r i t e d . Newman (1940) suggests that t h i s i s more l i k e l y to be the case f o r d i z y g o t i c than f o r monozygotic twins, since d i z y g o t i c twinning depends on double o v u l a t i o n i n the mother. He c i t e s evidence that multiple-egg b i r t h s tend to run i n f a m i l i e s , implying a genetic influence, but he states that he knows of no evidence to suggest that monozygotic twinning i s i n h e r i t e d . R i f e (1940) found that left-handedness was no more frequent among the immediate r e l a t i v e s of d i z y g o t i c twins that i n non-twin f a m i l i e s , and was unaccountably le s s frequent among the immediate r e l a t i v e s of monozygotic twins. These observations suggest that there i s no common genetic basis f o r left-handedness and twinning, but that a tendency to produce twins, perhaps i n part genetic, might i n d i r e c t l y increase the proportion of left-handed progeny. Such an inf l u e n c e would presumably be very weak. The strongest point to emerge from the above genetic twin studies appears to be that twins, probably because of prenatal str e s s e s , are more l i k e l y to be non right-handed than are s i n g l e t o n s . This was the r a t i o n a l e used f o r the s e l e c t i o n of twins as- subjects i n the present study. By working with a high-r i s k group more non right-handers were a v a i l a b l e , which made i t reasonable to expect some d i s c e r n i b l e d i f f e r e n c e s between r i g h t and non right-handers. In order to understand f u r t h e r the nature of these p e r i n a t a l f a c t o r s and th e i r r e l a t i o n s h i p to handedness, the di s c u s s i o n now focusses on twins and t h e i r early development. 18 The twin method of study was first defined by Galton (1875). Interest in twin types appears to have begun when i t was noted that in some instances of human twinning the two individuals resembled each other very closely. The concept developed that "identical" twins came from a single fertilized ovum and "fraternal" twins came from two separate ova. The first circumstantial evidence for this hypothesis was that single ovum twinning had been observed in the developing embryos of fish and birds. Methods now used to determine the zygosity of twins include observations of morphological characteristics, sexing of twins, blood groups, and skin grafting. Zygosity can be deduced from physical similarity and other characteristics whose mode of inheritance is known. If a pair of twins differs in a single inherited trait, such as sex, eye colour, or blood group, they are considered dizygotic. However, since dizygotic twins can share many traits (Bulmer, 1970), a pair of twins can never be proved to be monozygotic, except by skin grafting. Establishing zygosity in twins at birth is difficult. It could not be established in 20% of cases at Chicago Lying-in Hospital, a center specializing in twin births (Potter, 1963). Differentiation of twin-types is important because environmental influences appear to effect the different types in various ways. Embryological studies have explained the process of dizygotic and monozygotic twinning. The number of mature ova released from the ovary is apparently determined by a balance between the action of pituitary gonadotropins, which stimulate the development of ovarian follicles, and the inhibitory action of the ripening follicles on the maturation of other follicles. The large Graafian follicle in the ovary is thought to inhibit other ovarian follicles. If such inhibition fails due to endocrine imbalance, such as excessive 19 pituitary stimulation, two or more ova may be realesed. Dizygotic twins, derived from the independent release and subsequent fertilization of two ova, are genetically as dissimilar as any other siblings but have the same age and are in utero at the same time. They may even have different fathers (Andreassi, 1959). In general, dizygotic twins occur in three out of every 1,000 births. The incidence of dizygotic twinning is about eight in 1,000 in Caucasians. Negroes have dizygotic twins about twice that often, but Mongoloids have them less than half as frequently (Bulmer,1958). Whereas a l l monochorial twins are monozygotic, only 70% of identical twins are monochorial; the remaining 30% are dichorial with either fused or separate placentas (Wynn, 1968). Monozygotic twins are produced from a single fertilized ovum which cleaves in half at any of the preimplantation stages. It is generally assumed that monozygotic twins are genetically identical, apart from the remote possibility of somatic cell mutation. However, twins vary more or less in certain aspects since neither monozygotic nor dizygotic twin fetuses-develop in utero under identical circumstances. When two blastocysts implant near each other, placental growth becomes more lateral and eccentric in order to sustain fetal growth. The effect of crowding in utero is more apparent in fused dichorial placenta than in separate dichorial condition. Monochorionic twins are monozygous and therefore of the same sex, except in instances when the chorionic partition breaks down in a dichorial pair. Different-sex twins are dizygotic and dichorionic. Vascular anastomosis often occurs in monochorial placentas, most commonly as anastomosis on the placental surface, or an arterior-venous shunt between the fetal circulations 2 0 whereby an artery from one fetus supplies a cotyledon of the placenta which is drained by a vein from the other fetus. In monochorionic twins, birthweight is particularly low and fetal growth, retardation relatively frequent. The characteristics and malformations of same-sex dichorionic twins, of whom one-third may be assumed to be monzygotic, are not usually intermediate between the all-monozygoti'c monochorionic and the all-dizygotic opposite-sex groups, but rather are similar to the latter. Monoamniotic twins occupy a common amniotic sac. They may derive from division of the blastocyst after the formation of the amnion. Usually the twins are separate, but incomplete division of the embryo at this stage may give rise to cojoined twins. One percent of a l l twins are monoamniotic. Since monoamniotic twins are a l l monozygotic and since one-third of a l l twins are monozygotic, Bulmer (1970) estimated the frequency of monoamniotic twins among monozygotic twins at about four percent. Factors affecting multiple pregnancy include heredity, parental age and parity and nutrition. The occurrence of twinning is maximal among Negroes and minimal among the Monogolian peoples, with Caucasians intermediate. Since there is considerable mixture of genetic material from white Americans to black Americans, i t may be assumed that dizygotic twinning is more frequent in pure-bred African Negroes (Bulmer, 1970). In the United States, Canada and Great Britain, about one out of every 83 births is a twin birth. In Belgium, twins occur in one out of every 56 births, while in China the rate is only one in 300 (Say, Gungor & Durmes, 1967). Monozygous twinning is most common among Chinese and Malays (Chunn, 1970) whereas dizygous twinning predominates in western countries. Dizygotic 21 twinning is partly due to increased levels of pituitary gonadotropins which cause a higher incidence of double ovulations. If such traits are partly inherited they can only express themselves in women because they act through the ovaries. It has been suggested that twinning frequency is seasonal (Edward, 1938) and that continuous exposure to light in Northern Finland leads to hypothalamic stimulation, with resultant polyovulation (Tiroonen & Carpen, 1968). In Finland the peak of conception of twins is in July and the nadir in January. Although Timonen & Carpen show that multiple pregnancies have a stronger seasonal variation than single ones, Selvin and Janerich (1972) f a i l to find a seasonal twinning rate in New York State. They, suggest that this may be the result of differences in the composition of the populations studied. Maternal age is correlated with the frequency of dizygotic twinning. The maximum is reached at 39 years of age and then falls abruptly. (Guttmacher & Kohl, 1958). The increase may be partly due to increasing levels of gonadotropins and higher incidence of double ovulations, whereas the f a l l in twinning during menopausal years is probably due to decline in ovarian function. Multiple births increase with increasing ages of father up to 34-48 years of age and are fairly constant thereafter (Pollard, 1969). This correlation may be due to the high correlation with age of mother which is the determining factor. The frequency of dizygotic twinning increases with parity perhaps due to permanent changes in the activity of the pituitary or the ovary during pregnancy. The frequency-of monozygotic twins does not appear to be affected by parental age. An increased dizygotic twinning rate has been found among illegitimate maternities with maternal ages between 25 and 39 (Erickson & Fellman, 1967). 22 The twinning frequency has also been found to be greater when women conceive within the first three months after marriage (Bulmer, 1970). Nutrition is an important factor in twinning. Undernutrition causes a decrease in l i t t e r size in polytocous mammals and a decrease in dygotic twinning in man. Dizygotic twinning decreased during the Second World War in those countries which suffered from undernutrition (see Hafea, 1974). This decrease is probably due to diminished secretion of gonadotropin and to a decline in healthy semen characteristics. The growth rates of the fetus and its component organs and tissues vary during different stages of intrauterine l i f e . For example, during early fetal development, the cephalic region grows rapidly and, consequently, the fetal head is disproportionately large. At birth, the head and limbs are relatively more developed than the muscles. Whereas certain fetal organs grow very rapidly early in prenatal l i f e , others begin to grow later. For each organ and tissue the growth rate increases to a maximum, then declines. These maximal rates of growth occur in a definite sequence: fir s t , the central nervous system, then the skeletal system and lastly muscle and adipose tissue. When the fetus is deprived of nutritional supplies, some fetal organs are affected more than others according to the stage of pregnancy when nutritional deprivation occurs.; Some organs, however, seem to have nutritional preference regardless of stage deprivation. In growth-retarded fetuses, while the brain and heart are the least likely to suffer, the liver and thymus are more so affected (Gruenwald, 1963). The parameters of fetal growth and development do not necessarily follow the same pattern in a l l populations. Negro neonates, for example, are smaller 23 i n s i z e but more developed i n t h e i r locomotor modalities than Caucasian infants of the same conceptional age (Gerber, 1957). Certain maternal and f e t a l conditions may cause f e t a l growth r e t a r d a t i o n ; these include e.g. hypertension during pregnancy, chronic f e t a l disease, and e r y t h r o b l a s t o s i s f e t a l i s due to Rh i n c o m p a t i b i l i t y . In mu l t i p l e pregnancies, r e t a r d a t i o n i n f e t a l growth i s probably due to lack of n u t r i e n t s . Monochorial twins s u f f e r more growth r e t a r d a t i o n than d i c h o r i a l twins and also r i s k the tra n s f u s i o n syndrome. Retarded f e t a l growth has a small but l a s t i n g e f f e c t on postnatal p h y s i c a l development. Infants with birthweights under 2270 g have an increased chance f o r p h y s i c a l and mental handicaps ( D r i l l i e n , 1968). Several c r i t e r i a are used to evaluate f e t a l growth, such as birthweight, t o t a l body length, s i t t i n g height, or head circumference. Birthweight i s influenced by the i n t e r a c t i o n of several f a c t o r s , i n c l u d i n g heredity, sex, p a r i t y , maternal s i z e and n u t r i t i o n , p l a c e n t a l s i z e , and socio-economic status. Sex d i f f e r e n c e s i n birthweight are presumably inherent i n the fetus. The d i f f e r e n c e i n birthweight between f i r s t b o r n and l a t e r i nfants i s caused by changes i n the uterus and elsewhere i n the mother (Gruenwald, 1967), in c l u d i n g possible increased maternal body weight and the higher g e s t a t i o n a l blood glucose l e v e l associated with increased age and p a r i t y ( 0 ' S u l l i v a n , G e l l i s & Tenney, 1965). Maternal height and heart s i z e are p o s i t i v e l y c o r r e l a t e d with birthweight (Raiha, 1964). Pla c e n t a l and f e t a l growth are hig h l y c o r r e l a t e d . Throughout the f e t a l stage of i n t r a u t e r i n e l i f e , the fetus gains i n weight more r a p i d l y than the placenta. The f u n c t i o n a l e f f i c i e n c y of the placenta per unit weight increases 24 u n t i l i t reaches a maximum at a g e s t a t i o n a l age of 36-37 weeks; ther e a f t e r , degenerative changes preclude fur t h e r increases i n e f f i c i e n c y (Gruenwald, 1967). Twins are at a double disadvantage compared with singletons since they are both retarded i n growth and born e a r l i e r . The average birthweights of singletons and twins are 3180 g and 2270 g r e s p e c t i v e l y . Thus the t o t a l f e t a l birthweight f o r twins i s about 4550 g. As b i r t h number increases, gestation times decrease. Twins thus appear to be negatively predisposed to prenatal stresses. These stresses are both q u a n t i t a t i v e l y and q u a l i t a t i v e l y d i f f e r e n t from those undergone by singletons. The inherent hazards of mul t i p l e gestations subject both mother and o f f s p r i n g to r i s k s beyond those of usual pregnancy; maternal complications are greater and more severe (e.g. Misenhimer & K a l t r e i d e r , 1978) and f e t a l development i s more r e s t r i c t e d , with accompanying unique formational problems (e.g. Benson, 1976). Twinning i s often associated with such problems as s t i l l b i r t h (Manlan Scott, 1978), premature labour (Mooney, 1970), f e t a l d i s t r e s s (Daw & Walker, 1975), f e t a l t r a n sfusion syndrome ( K o i v i s t o , Jouppila, Kauppila, Moilanen & Y l i k o r k a l a , 1975), asphyxia neonatorum (Ho & Wu, 1975), hypoglycemia (Manlan et a l , 1978), low birthweight (Powers, 1973), small s i z e f o r g e s t a t i o n a l age (Chamberlain & Davey, 1975) and long-term growth re t a r d a t i o n (Hehenaur, 1971). Twins also evidence more language r e t a r d a t i o n ( M i t t l e r , 1976), s t u t t e r i n g (Godai, T a t a r e l l i & Bonanni, 1976), c e r e b r a l palsy (Yue, 1955), delayed 25 intellectual development (Mehrota & Maxwell, 1949), negative self-concept and reduced sociability (Zazzo, 1976), less goal-orientation (Kranitz & Welcher, 1971) and less educational attainment (Mittler, 1971). Many twins do not survive to birth. The perinatal mortality rate in twins is comparatively high, i.e. about 12%, whereas in singletons i t is only three percent (Medearis et al, 1979). Monochorionic (hence MZ) twins are viably at a much greater disadvantage (26%) than are dichorionic twins (9%). Monamnionic twins have a higher mortality rate (50%) but are also the least frequent(+ 1%). Death rates are the same (14%) in white and black twins of large populations studied by Fujikura and Froehlich (1971). It was highest in male pairs and death of both twins was most common in monochorionic placentation. Male-female pairs had the best chance of survival. Factors determining high rates of perinatal death are multiple and have been extensively analyzed. Unfortunately, the conditions examined in these series of studies show much variation. According to Manlan et al. (1975)t . the high mortality rate of twins relates primarily to their increased frequency in prematurity. Prematurity is that condition whereby the infant is born after less than thirty seven weeks of gestation. The gestational age is often calculated by counting the number of days from the first date of the last menstrual period to the date of delivery. Other methods used to estimate gestational age include sonography, measurement of the proportion 26 of the fetal hemoglobin in the blood and amniotic fluid bilirubin, urea and creatinine analysis (Mandelbaum & Evans, 1969) . Radiological determination of ossification centres (Scott & Usher, 1964) and neuro-logical examination (Illingworth, 1963) of the neonate are also used. In autopsies after perinatal death, information may be obtained from the weights and degree of maturation of various organs. Ho and Wu (1975) showed that only 64% of twins deliver at term, and that 91% of neonatal deaths occur in preterm infants. Many studies (e.g. Bleker, Breur & Huideloper, 1979) indicate the mean gestational age for twins is less than i t is for singletons, i.e. 33 weeks as compared to 37 weeks. Hendricks (1966) reported that 75% of the perinatal mortalities in this group were in infants born prior to 30 weeks gestation. The mortality rate of this group was 95.6%. In twins born between 30 to 33 weeks, the mortality rate was 25.7% while for those born between 34 to weeks, the rate dropped further to 6.25%. Those in the 38+ weeks group, evidenced a rate of 1.9%. However, even this low percentage was s t i l l more than double the perinatal mortality rate for singletons born at those weeks of gestation. In response to the question, "why do twins deliver early?", McKeown and Record (1952) postulated that prematurity is related to uterine distensibility. They noted that in guinea pigs and rabbits, large litters are associated with shorter gestations and low individual birthweights. In guinea pigs, the "crowded" uterine horn produces offspring that are of a lower mean birthweight than their littermates from the opposite and less crowded horn. McKeown and Record reviewed a l l b i r t h s i n Birmingham, England i n 1946 and surveyed mu l t i p l e pregnancies i n the United Kingdom. They observed that i f d i s t e n s i b i l i t y were the only determinant of the time of d e l i v e r y , the combined weight of the " l i t t e r " should always be equal to some f i x e d amount, but t h i s i s not the case. McKeown and Record postulated that as gestation progresses, the uterus becomes i n c r e a s i n g l y s e n s i t i v e to d i s t e n t i o n . Thus, as mean combined birthweight increases from 7.53 pounds for singletons to 12.28 pounds f o r quadruplets, the means length of gestation decreases from 326.8 days to 280.5 days. While these data are compatible with the hypothesis that u t e r i n e d i s t e n s i b i l i t y i s the f a c t o r l i m i t i n g the length of gestation and l i t t e r weight, i t i s not conclusive. As these authors l a t e r point out (Eckstein, McKeown & Record, 1955) t h e i r data are compatible with the hypothesis that f e t a l t i s s u e s outgrow the supply of some e s s e n t i a l f a c t o r such as hormone, nu t r i e n t , or blood supply and thus change the rate of weight gain. F e t a l weight i n guinea pigs depends upon the number of fetuses occupying the same uterin e horn ( i . e . the l o c a l e f f e c t ) and also upon the number of fetuses occupying the opposite horn ( i . e . the general e f f e c t ) . Thus the f e t a l weight i s determined not only by how "crowded" i s i t s own ute r i n e horn, but also upon the number of fetuses present i n both horns. This growth pattern i s consistent with the hypothesis that f e t a l blood or nutrient supply may also be a l i m i t i n g f a c t o r . Others o f f e r corroborating evidence from animal studies (Duncan, 1969; Wigglesworth, 1964) . Human i n v e s t i g a t i o n also suggests that blood flow may 28 be a limiting factor in twin pregnancies. Morris, Osborn & Wright (1955) found evidence of diminished uterine blood flow in women pregnant with twins. They measured the clearance rate of sodium (Record, McKeown & Edwards, 1970) injected into the uterine wall, and interpreted this as a measure of effective uterine blood flow. They found that pre-eclamptics carrying a single fetus had a much longer clearance time than did normal single pregnancies, and that the clearance time in normal twin pregnancies was also somewhat prolonged. This observation is of interest for at least two reasons. First, the decreased uterine blood flow demonstrated in the twin pregnancies seems consistent with animal data and could be causally related to decreased birthweight in twins. Second, the fact that "normal" twin pregnancies are midway between normal and pre-eclamptic singletons might point to an explanation of the inordinately high rate of pre-eclampsia in twin pregnancies. The Helsinki group has studied the constraints that the cardiovascular system imposes upon gestation. They have measured the cardiac work capacity needed to successfully carry a pregnancy and have tried to improve this capacity when i t has been limited. According to the Helsinki group, cardiac size can be calculated from chest x-rays, and this calculated cardiac size and hemoglobin concentration can be used to estimate "work capacity". Mothers with small work capacities and mothers whose work capacity does not increase during pregnancy tend to deliver premature babies. It is felt that resting the mother with marginal work capacity decreases the amount of blood going to other vascular beds and increases the perfusion of the uterus and placenta. The Helsinki group offers considerable data consistent with this hypothesis (for an extensive review see Raiha, 1968) but their studies have been criticized for being uncontrolled (Abramowicz & Kass, 1966) . 29 Other workers have not been able to replicate a l l of their results (e.g. Terris, Gold & Schwarz; 1965). Barter et al (1965) reported on the use of bed rest for twin pregnancies which had occurred over a preceding ten years. Out of 252 twins, 225 mothers did not rest; these served as controls. Among the "treated" twin pregnan-cies, 37 mothers were placed on bed rest. Results showed that 52.4% of the "control" infants were low birthweight (less than 2501 g) while only 35.5% of the "bed-rest" infants were such. The mean birthweight of the treatment group was 628 g above that of the control group. Perinatal mortality (10.9% in the control group) f e l l to 8% in the "bed rest" group. Misenhimer et al. (1978) found that maternal bed rest reduced activity until the thirty-sixth week of pregnancy and resulted in less premature deliveries, reduced perinatal mortality and increased fetal weights. However, selection bias may be operating in United States' studies of bed rest mothers. Because of the present health system, American patients who rested were probably different (more affluent, more compliant and more health conscious) than the patients who did not rest. Cross-cultural investigations are needed to clarify present results. Low birthweight is an additional perinatal stress on twins. About 55% of twins (Ho & Wu, 1975) are low birthweight, i.e. have an individual birthweight of less than 2501 g. In singletons, about seven percent are in this category. Low birthweight is partly the result of premature delivery. Some investigations believe that the type of placentation principly determines the fetal growth rate (Fujikura & Froehlich, 1971). 30 Zygosity and sex have also been r e l a t e d to birthweight (e.g. Kohl & Casey, et a l . ; 1975). In like-sexed p a i r s , the f i r s t born i s about 40 g heavier than the second and male p a i r s are us u a l l y heavier than female p a i r s . In mixed-sex p a i r s , the male i s the heavier of the two. When the male i s second born, the weight d i f f e r e n c e i s about 100 g, but when the male i s f i r s t the d i f f e r e n c e i n male-female weight i s about 150 g. In general, the f i r s t i n f a n t i s heavier than the second, except i n the female-male p a i r s where the male's mean weight exceeds the f i r s t i n f a n t ' s (female) by 95 g. The twin who i s heavier at b i r t h i s l i k e l i e r to be heavier during childhood (Bakwin, 1973), and to have a higher tested i n t e l l i g e n c e (e.g. Pencavel, 1976; Scarr, 1969). Birthweight may also a f f e c t p e r s o n a l i t y development i n l a t e r years. A l l e n (1971) has in d i c a t e d that the lower birthweight twin i n i t i a l l y receives more a t t e n t i o n from, and i s l a t e r more dependent upon h i s parents than i s the heavier twin. Low birthweight twins appear to be at high r i s k f o r developing cerebral palsy. Yue (1955) reviewed 301 cases of cerebral palsy and found that nine percent were twins, while only two percent of the general population might be expected to be twins. The mean birthweight of these p a l s i e d twins, 1990 g was considerably l e s s than the mean birthweight of a mean population of twins. The smaller twin was p a r t i c u l a r l y disposed to palsy. B i r t h order has been linked to s p e c i f i c p e r i n a t a l s t r e s s e s . Numerous studies have inquired whether the second d e l i v e r e d twin i s inherently at a 31 disadvantage. When stillborn macerated twins are removed from statistics, most authors find a slightly higher death rate of the second twin, some, however, do not (Potter, 1964, 1968) . A conservative view of the discrepancies would be that obstetric practice, facilities and competence vary widely and that, given optimal care, no appreciably different mortality between the twins occurs. Surgical intervention is higher in the second twin; length of anaesthesia, hypoxia, etc., may also affect the outcome. Optimal delivery is around 15 minutes after the first twin, and when 30 minutes have passed, the second fetus is considered "retained". His survival is then lower than proportional to the interval (Adeleye, 1972) . Most authors (Allen, 1965) acknowledge that noteworthy fetal anomalies are about twice as frequent in twin pregnancies. Prolapse of the cord and rupture of vasa praevia with exsanguination of one twin is more common (Whitehouse & Kohler, 1950), the latter because velamentous insertion of the cord occurs in seven percent as compared to one percent to singletons (Benirsche & Driscoll, 1967) . Twins rarely interlock during delivery (Khunda, 1972) . This complication occurs perhaps once in 1,000 twin deliveries and has a correlated fetal mortality of 31%. Although pre-eclampsia is more common in twin gestation, i t rarely accounts for the increased perinatal mortality. Most poorly understood is the association of twinning with hydramnios, this diagnosis having been made in 12.5% of Farrell's 1,000 twin deliveries (Farrell, 1964) . The perinatal mortality in this group was 41%, others are cited as reporting between 23% and 87%. Although this complication is high in severely malformed conceptuses and often associated with considerable 32 prematurity, this was not the case in Farrell's study and the relation to multiple pregnancy is poorly understood. Hydramnios is more common in monozygotic twins and is usually associated with the larger twin (Krauer, 1964) . This is often related to the development of the "transfusion syndrome", but generally the vascular network of the placenta is inadequately studied to verify this concept. As shown above, twins are ipso facto exposed to a hazardous early environment. Factors prevalent during gestation, delivery, and the post-natal period appear to have a major impact on their later development. One such later development may be handedness. Assessment techniques have therefore been devised to identify infants at risk throughout the perinatal period, i.e. the twelfth week of gestation throughout the twenty-eighth day after birth (Behrman, 1973) . These techniques score perinatal, natal, and neonatal biological events along with neonatal behavioral performance in an additive fashion so as to sort out those infants who have a high probability of manifesting a sensory or motor deficit or a mental handicap (Parmelee, Kopp & Sigman, 1976) . The following study incorporates such assessment techniques in order to investigate associations between specific perinatal factors and handedness in twins. The hypothesis is that the most optimal perinatal profile, consisting of 30 prenatal and postnatal variables, is associated with right-handedness at six and one-half years. The non right-handed group should have a higher index of perinatal difficulties than the right-handed group. Handedness was assessed at the age of six and one-half years as this is the age at which handedness has been shown (e.g. Gesell & Ames, 1947) to stabilize. 33 I I . Method Subjects Subjects were 66 twins selected from the U.B.C. Department of Pa e d i a t r i c s Premature's Growth and Development Survey. This i s a l o n g i t u d i n a l survey of ne u r o l o g i c a l and opthalmic disorders i n c h i l d r e n of low birthweight. The low birthweight population included 502 ch i l d r e n born i n Vancouver General H o s p i t a l during the period from September, 1958, to May, 1965. Their birthweight was below 2041 g (4% l b . ) . The comparison group consisted of 207 c h i l d r e n born i n the same h o s p i t a l from October, 1964, to March, 1966. Their birthweights were greater than 2500 g (5% l b . ) . The comparison .infants were selected i n such a manner as to r e f l e c t the s o c i a l c l a s s d i s t r i b u t i o n of the low birthweight i n f a n t s . The s o c i a l c l a s s of the c h i l d r e n was assessed by the Hollingshead and Redlich (1958) s c a l e . Five classes were used, with Class I representing high SES and Class V representing low SES. Seventy to 75% of the c h i l d r e n i n both groups f e l l into S o c i a l Class IV and V. Of the o r i g i n a l 709 c h i l d r e n , 122 were twins. Of these, 13 died during the neonatal period and 43 were dropped from the survey f o r various reasons (e.g. death of co-twin, change of residence). T h i r t y - t h r e e p a i r s were followed to the age of s i x and one-half years. Thirty-one p a i r s were from the low birthweight group and two p a i r s were from the comparisons. Among the 66 twins, 37 were male and 29 were female. No attempt was made to d i f f e r e n t i a t e between uniovuluar and binovuluar twins as d e t a i l e d observations (e.g. blood group testing) had not been completed i n the majority of p a i r s . 34 Materials For each subject, the following materials (see Appendix) from the U.B.C. Department of Paediatrics Premature's Growth and Development Survey were used: Prenatal Record, Labour and Delivery Record, Nursery History, Neonatal Examination, Neonatal Neurological Examination, 6% Year Examination. Risk score items for the f i r s t five scales are described as follows: Prenatal Record The Prenatal Record determines the presence or absence of optimal conditions relating to maternal factors, e.g. reporduction, medical and family histories as well as factors relating to the present pregnancy. Labour and Delivery Record The Labour and Delivery Record is composed of 55 items relating to aspects of labour and delivery, e.g. duration of labour, medications. An optimal condition is defined for each item. Nursery History The Nursery History is also based on an optimal score concept and includes 29 items related to conditions in the nursery as well as to indicators of the infant's physiological status, e.g. motor activity, medications, diseases. Neonatal Examination The Neonatal Examination is also based on an optimal score concept and examines the infant's status on 46 items. These items denote the presence or absence of respiratory difficulties, metabolic disturbances, seizures, surgery, etc. Neonatal Neurological Examination The Neonatal Neurological Examination evaluates infants with, respect to muscle tone, reflex patterns of behaviour, EEG, etc. on 64 items. Basically, 35 the above scales assess the occurrence of complicating factors in the perinatal period. The items used reflect increased risk of mortality and therefore are presumed to be significant factors in an infant's later development. The system is self-weighting. As a result, the severity of the events are relfected in the deviance of the score, e.g. "how far from the optimal are the sequence of factors arising postnatally?" Procedure Thirty perinatal variables were selected from the first five records (e.g. U.B.C.'s Prenatal, Labour and Delivery, Nursery, Neonatal, Neonatal Neurological). Selection of variables depended upon whether or not there was general medical agreement (for a review of high-risk predictors see Parmelee, Sigman, Kopp & Haber; 1976) and/or psychological implications as to their high-risk relevance (e.g. anoxia has been linked (Bakan, 1975) to brain damage and non right -handedness), and whether or not data were complete on these variables (e.g. Apgar scores were not included because of excess missing observations. Apparently, when a twin was in jeopardy, the attention of delivery room personnel was directed at saving the baby, not scoring i t ) . Subjects were then evaluated according to whether or not each perinatal risk factor indicated by the variable was present. These scores, reflected the possibility that a subject, because of having been exposed to hazardous biological events during the perinatal period, could be considered at risk for a later developmental disability (Parmelee, et al., 1976). The scores were also used as a potential indicator of his handedness behaviour at six and one-half years. 36 After perinatal risk scores were determined, the handedness of each subject was assessed from information in the "Handedness" scale (see Appendix F) of the U.B.C.'s Growth and Development Survey's 6% Year Examination. This scale contains- the following tests of handedness: 1) draw or write with a pencil, 2) throw a bal l , 3) cut with scissors, 4) wind a stop-watch, 5) turn a door knob. Although a l l five activities allow the examiner to observe spontaneous hand preferences, i t was noted in retrospect that the test would be improved i f the third item, "cutting with scissors" were removed. Given the nature of the way scissors are constructed, this task may handicap non right-handers. An effort was made to deal with this issue by providing both right and non right-handed scissors, but this task, may inhibit spontaneous performance for the non right-handers and thus offer a potential bias to test results. This issue, although relevant to future applications of the U.B.C. handedness test, has l i t t l e or no consequences for the present study where the handedness scale was dichotomized into right and non right categories. The U.B.C. handedness test nonetheless combines many features of the most perferred tests. For example, Thompson & Marsh. (.1976) showed that the best test for hand preference are those in which spontaneous use is observed (specifying spontaneity is explicitly in contrast to requiring that the subject take some sort of time test with each hand or utilizing some such measures as strength, of grip, a notoriously fallible approach (Clark, 1967)). The U.B.C. test also follows the direction of Bryden (1977) who showed that such similar activities give a reliable assessment of handedness. Because the U.B.C. test is a motor test i t successfully avoids the pitfalls of written questionnaires whose responses may not be comparable to behaviours manifested in real l i f e 37 situations (Annett, 1970). The U.B.C. items (from Harris, 1958), have also been validated (Annett, 1970) against a test of manual speed. Thus, the reliability and validity of the U.B.C. instrument, coupled with a relatively rapid administration (less than five minutes) appears to make i t a useful device for assessment of handedness. To administer this test, the examiner seated the child at a table, on the centre of which was placed a ball, a watch, scissors, a pencil and papers. For the fir s t four tests the child was simply asked to perform the required action, e.g. "Please write your name on the paper". For the last test, the child was asked to get up and walk over to a door (on which the knob was on the right side) and to open i t . He was then asked to proceed to another door (on which the knob was on the left side) and to open i t . In the original U.B.C. testing situation (i.e. 1965), Harris (1958) rules were used and a twin, after performing the tasks, was classified into one of five possible categories (e.g. "slightly l e f t " , "slightly right" etc.). However, for purposes of the present study a different categorization method was employed. Here a twin was classified as either right or non right-handed (i.e. i f a twin had originally been classified as "strong right" this now indicated a right-hander, whereas classification in any of the other six categories indicated a non right-hander). The rationale for the creation of these two dichotomous categories was that in the present study the sample was too small to effectively analyze seven categories, and that i t was basically a deviation from the handedness norm that was of interest. III. Results An overall chi-square indicated that there were no sex vs. handedness differences. On the basis of this finding i t was decided to combine males and females for the analysis. Thirty variables which were gross indices of perinatal status (see Parmelee, 1976) from the U.B.C. Growth and Development Survey were examined for the purposes of this analysis. Phi coefficients were calculated for the 30 variables in an attempt to assess the strength of variables in relation to non right-handedness. Table 1 presents, the phi coefficients for the 30 variables of which the following are significant at .05 level: maternal diabetes, maternal age, medications during pregnancy, and toxemia. It should be noted that because of the dependencies inherent in the data this level of significance and any of the others reported are only appropriately correct. Table 2 provides percentages for non right-handers in the optimal and non optimal classifications of perinatal high-risk variables. A l l of the 30 variables were then categorized according to perinatal complications of mother or child. These categories were: Mother's Prenatal Problems, Infant's Postnatal Problems, Infant's Breathing Problems, Infant's Prematurity status, Mother's Weight Problems and Infant's Neurological Status. 2 A Hotelling T on the six perinatal categories-with handedness as the independent variable - revealed a significant mean difference. (F(6, 59) = 2.96, p ^ .05), therefore indicating that right-handed and non right-handed Ss differed on their mean ratings across a l l categories considered simultaneously. The non right-handed group also received a higher mean score on each of the six categories considered separately. This indicated that the non right-handers had more perinatal difficulties than did the right-handers TABLE 1 39 Phi coefficients for perinatal risk factors arid handedness Perinatal Risk Factors Non right-handedness Mother's Prenatal Problems Phi^ coefficients Diabetes Pelvic disproportion Age Infection and/or acute disease Noninfectious illness and/or anomaly Metabolic disturbance Medication (antibiotics) Medication (steroids/endocrines) Surgery Anaemia Mother's Weight Problems Toxemia .26* Weight gain .04 Urinary infection .13 Infant's Prematurity Status Gestational age .06 Weight .13 Infant's Neurological Status E.E.G. .08 Neurological impression .04 Infant's Breathing Problems I.V. glucose during labour Demeraol " " Tranquilizers and antibiotics during labour Ventilatory assistance Respiratory distress Infant's Postnatal Problems Motor activity .11 Reflex responses .23 Eye movement abnormalities .10 Traction " .02 Head structure " .20 Ear structure " .10 Face structure " .20 Extremities and joints " .23 * p../.05 .27* .07 .25* .23 .13 .11 .09 .30* .14 .10 .07 .08 .08 .08 .09 TABLE 2 40 Percentages for perinatal profiles, and nori righr.-handedness. Non right - hariders Perinatal Risk Factors Mother's Prenatal Problems Diabetes \ Pelvic disproportion Age Infection and/or acute disease Noninfectious illness and/or anomaly Metabolic disturbance Medication (antibiotics) Medication (steroids/endocrines) Surgery Anaemia Mother's- Weight Problems Toxemia Weight gain Urinary infection Infant's Prematurity Status Gestational age Weight Infant's Neurological Status E.E.G. Neurological impression Infant's Breathing Problems I.V. glucose during labour Demeraol " Tranquilizers and antibiotics " Ventilatory assistance Respiratory distress Infant's Postnatal Problems Motor activity Reflex responses Eye movement abnormalities. Traction " Head structure " Ear structure " Nose structure " Extremities Negative profile 89.47 25.00 68.42 31.25 41.17 63.63 16.67 73.68 41.17 40.02 83.67 52.94 21.05 78.23 74.21 75.00 77.78 74.20 52.01 64.75 52.63 52.63 50.00 35.72 20.00 11.76 73.68 45.56 45.56 32.40 Optimal profile (%) 10.52 75.00 10.52 68.75 58.82 36.67 83.33 26.31 58.82 9.98 16.33 47.05 78.94 21.77 25.79 25.00 22.02 25.80 47.99 35.25 47.37 47.37 50.00 64.28 80.00 64.71 26.31 54.44 54.44 67.60 41 on a l l of the categories considered. Tahle 3 presents the group means for these six perinatal risk categories.. Paired comparisons were performed on a l l the six variables, the results of which were not significant at the .05 level. In order to examine how well the six categories predicted handedness, a discriminant function analysis was performed, and was, of course, significant. As is evident from Table 3, only three Perinatal Risk categories contributed the most towards determining the handedness of the Ss^ . These categories were Mother's Prenatal Problems, Infant's Breathing Problems and Infant's Neurological Status. IV. Discussion Analysis of the data indicated support of the hypothesis that non right-handed Ss tended to have a higher negative profile, as was indicated by the Hotelling T^  on the six perinatal risk categories. Again, because of dependency in the data, any significance is to be viewed with caution, as a l l inferential tests have unknown significance levels. Although, pair-wise comparisons indicated that Ss did not differ significantly on any one of the six categories, i t is possible that a larger sample size would have resulted in a significant finding. TABLE 3 Discriminant function weights and group means  for risk categories by handedness Perinatal Risk Categories- Group Means Discriminant Function Right-handed Non Right-handed Coefficients Mother's Prenatal Problems 2.57 3.95 .58 Infant's Postnatal Problems .68 .95 .14 Infant's Breathing Problems 1.55 1.63 .68 Infant's Prematurity Status .38 .37 .01 Mother's Weight Problems 1.81 2.89 .10 Infant's Neurological Status 1.28 1.95 .41 43 Most recent perinatal high risk assessment techniques employ a clustering of seemingly unrelated events (e.g. toxemia/infant's head structure) in order to produce a cumulative effect on the ultimate infant risk. In the present study only those perinatal risk factors upon which there was general medical agreement regarding their importance were included. The four maternal factors which appeared to be contributing most in the direction of significance, i.e. diabetes, age, toxemia and medication.? are ones quite often associated with infant risk. Lark and Lark (1972), in a study of 4,606 infants, identified diabetes as a major prenatal factor associated with negative birth conditions. Fetal overgrowth, insufficient placenta, prematurity, are some of the more usual complications. Perinatal mortality is five times the average (average = 10% - 20%) in offspring of diabetic parents (Babson & Benson, 1966). In twins, this high diabetes-related mortality rate is confounded by other problems inherent in multiple births which also produce unusually high mortality rates. Mother's age is a common high risk predictor. Infants who are premature and of low birth weight are more commonly born to women under 20 or over 40 years of age. Generally, results show (Corney, Robson & Strong, 1972), that as maternal age increases, total birth weight increases. Regardless of gestational age, in severely retarded children the mean maternal age at birth has been shown (Ho & Wu-, 1975) to be higher than 44 that reported f o r mothers of normal c h i l d r e n . Akesson (1966) showed i n 395 sets of twins that the average maternal age was 39; considerably higher than the average maternal age (24) of si n g l e t o n s . C e r t a i n l y , the e f f e c t s of maternal age are complex, but as r e s u l t s of t h i s study suggest, twins appear to be at an i n i t i a l disadvantage with older mothers. Almost any type of medication administered during pregnancy has been re l a t e d (e.g. Gruenwald, 1970) to negative e f f e c t s on both mother and i n f a n t . Thus, i t i s not s u r p r i s i n g that t h i s r i s k f a c t o r emerged as one of the stronger p r e d i c t o r s . In the present U.B.C. study, the medications i n question ( i . e . endocrine preparations) are ones often p r e s c r i b e d . Toxemia i s perhaps the most common prenatal problem, and includes hypertension, generalized edema and d e f i n i t e p r o t e i n u r i a . I t has al s o been r e l a t e d to primary Caesarian s e c t i o n (Kuhl, 1975). In 230 twin pregnancies, Mooney (1970) reported that 24.7% of the mothers developed toxemia. This i s about four times the incidence f o r si n g l e t o n pregnancies. 8.8% of the 112 in f a n t s d e l i v e r e d to women with toxemia died, which compared with a 6.6% i n the non-toxemic group. However, the p e r i n a t a l m o r t a l i t y i n primigravidae with toxemia was nearly twice the p e r i n a t a l m o r t a l i t y i n multigravidae with toxemia. Twins again are therefore shown to be exposed to more severe than usual p e r i n a t a l conditions. I n d i v i d u a l l y , these four factors are important i n d i c a t o r s of p e r i n a t a l s t r e s s . Clustered with le s s common fa c t o r s they may be con t r i b u t i n g to an o v e r a l l negative p e r i n a t a l p r o f i l e , which may i n turn be a f f e c t i n g an infan t ' s motor development. One aspect of t h i s may be non right-handedness. 45 In the discriminant function analysis, three of the risk categories appeared to be contributing most to the classification of the Ss. The first category-, Mother's prenatal Problems, includes a variety of rather severe complications. It also includes three out of four of the best predicting individual risk factors. The importance of the pre-natal period on an infant's later development cannot be overstated. Factors acting during this time are crucial to his very survival, as this is the period of greatest mortality in childhood. Social, economic, and cultural influences are superimposed on genetic, metabolic and physical intra-uterine effects. The trauma of multiple pregnancy adds to the impact. Therefore, the emergence of this first perinatal risk category is not unusual. Infant's Breathing Problems, the second high-risk category to emerge as relevant in the discriminant function analysis differs from the first in that the separate phi coefficients associated with the items of this category are a l l rather low. McNemar (1962) has referred to variables of this sort as "suppressant variables" in that while these variables, have low correlations with the criterion, they nevertheless correlate with other predictors and consequently contribute to the overall prediction of the criterion variables. Infant's breathing problems have been identified by many studies (e.g. Koivisto et al., 1975) as being the most common cause of death, in twins. Neonatal respiratory distress appears to be related both to the premature development of the infant (.e.g. immature lungs, etc.) as well as to anaesthetics administered to the mother during delivery. Regarding the latter, twin deliveries are usually more complex and take a longer period of time. Thus, anoxia is a usual threat which, is related to brain damage. Bakan (.1975) has suggested that this relationship between birth stress and delayed breath results not only in damage to the brain, but inevitably in non right-handedness. 46 Perhaps- this is also occurring in the present sample. Certainly twin births are more traumatic than single births, and anoxia occurs more frequently -as does non right-handedness. Less than optimal neurological status is often associated with difficult deliveries. A poor neurological impression may indicate some amount of brain damage which could be exprected (if i t occurred in the appropriate area) to affect an infant's handedness. Again, twins more often experience difficult deliveries and more often show abnormal neurological status (Newman, 1940). In the analysis of individual items, the question of why only four were significant arises. One obvious explanation may be that the small sample size would not give much strength, to the more obscure variables. Another explanation is that many items in the U.B.C. scales are not current. The scales were created in 1950 and since then many new high, risk indicators have emerged (e.g. aspirin is now forbidden to pregnant women). Perhaps i f these newer indicators had been available for the present analysis significance would have been more common. Also relating to the need for better items is the fact that many of the variables in the U.B.C. scales are redundant. For example, in "maternal smoking" one item is dichotomous, i.e. yes/no answers are requested, whereas another asks dimensions of smoking, i.e. 10/20 cigarettes per day. Much, specific information is also lost due to the fact that many original answers are given in ranges (e.g. when were oral feedings started? less than 24 hours? from 25 to 48 hours?). Handedness measurements could also be 47 taken at an earlier age and be more precise. Studies are now suggesting neonatal occurrences of handedness, yet the U.B.C. scales do not assess handedness until age two. Other explanations for lack of significant factors and categories may be related to the scales themselves, which were constructed specifically for singletons. For example, i f zygosity testing had been included as a matter of routine, many interesting questions could have been asked. Particularly, i t would be relevant to know i f non right-handedness is more common in monozygotic than dyzgotic twins. Then the genetic vs. environmental question could be asked more clearly. The amount of prenatal bed rest required by mothers of twins would also be worthwhile, as much, of the literature is now suggesting this as a method of overcoming prematurity in multiple births. Sound-wave information (i.e. how early were twins diagnosed by this method? Were there any negative effects?) would also be another useful area of investigation. As shown earlier, the mortality rate in twins is high, and much of this mortality occurs at the time of birth. Developmental deficits are also a problem. Clearly, there is a need for high-risk assessment techniques similar to the U.B.C. scales, but they should be more current and designed specifically for twins. Questions regarding the use of handedness as a pathological indicator w i l l continue to arise. The clinician would be wise to treat this aspect of cerebral dominance as one of many signs to investigate and to interpret a handedness rating as meaningful only when i t coordinates with other aspects of an individuals background, behaviours and profile of abilities. Research is required to incorporate handedness into the current body 48 of knowledge about lateral cerebral specialization and Interhemispheric integration. 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Acta Neurologica et Psychiatrica  Belgica, 1967, 67, 1013-1020. Zazzo, R. The twin condition and the couple effects on personality development. Acta Geneticae Medicae et Gemellologiae, 1976, 25_, 343-352. 66 APPENDIX 67 Appendix A U.B.C. PRENATAL RECORD 68 UNIVERSITY OF BRITISH COLUMBIA DEPARTMENT OF PAEDIATRICS PREMATURE GROWTH AND DEVELOPMENT SURVEY PRENATAL RECORD CASE NUMBER (1) (2) (3) NAME OF CHILD: VGH UNIT NUMBER: NAME OF MOTHER: BIRTHDATE OF PREMATURE: VGH UNIT NUMBER: DATE MONTH YEAR (4) (5) (6) (7) (8) (9) HISTORY TAKEN BY: SOURCE(S) OF MATERIAL: DATE OF HISTORY: MENSTRUAL HISTORY COMMENTS AGE AT ONSET: (10) unknown 0 less than 12 years 1 12 or 13 years 2 14 or 15 years 3 more than 15 years 4 UNUSUAL INTERVAL BETWEEN PERIODS:(11) unknown 0 less than 21 days 1 21 to 28 days 2 29 to 35 days 3 more than 35 days 4 gross irregularity 5 UNUSUAL DURATION OF PERIOD: (12) unknown 0 less than 3 days 1 3 , 4, or 5 days 2 6, 7, or 8 days 3 more than 8 days 4 DYSMENORRHEA: (13) unknown 0 none 1 slight (no treatment) 2 moderate (treatment and working)3 severe (off work) 4 REPRODUCTIVE HISTORY NUMBER OF FULL TERM BIRTHS: (14) unknown 0 none 1 one 2 more than one 3 Excluding this premature pregnancy 69 PRENATAL RECORD COMMENTS REPRODUCTIVE HISTORY NUMBER OF PREGNANCIES: (15) unknown 0 one 1 two 2 three 3 four 4 five 5 six 6 seven 7 eight 8 nine or more 9 NUMBER OF ABORTIONS: (16) unknown 0 none 1 one 2 more than one 3 NUMBER OF PREMATURE BIRTHS: (17) unknown 0 none 1 one 2 more than one 3 NUMBER OF MULTIPLE PREGNANCIES: unknown none one more than one (.18) 0 1 2 3 NUMBER OF LIVING CHILDREN: unknown none one more than one (19) 0 1 2 3 MOTHER'S PAST MEDICAL HISTORY HEART DISEASE: unknown none present (20) 0 1 2 Describe any past illness HYPERTENSION: unknown none present (21) 0 1 2 CANCER: unknown none present (22) 0 1 2 70 PRENATAL RECORD MOTHER'S PAST MEDICAL HISTORY DIABETES: unknown none present COMMENTS (24) 0 1 2 NEUROMUSCULAR AND PSYCHIATRIC DISORDERS: (25) unknown 0 none 1 epilepsy 2 palsy 3 retardation 4 mental disorder - emotional 5 mental disorder - psychotic 6 other (blindness, deafness, speech defect) 7 CONGENITAL ANOMALIES: (26) (of distinct medico-social significance) unknown 0 none 1 present 2 HOSPITALIZATION (OTHER THAN PREGNANCY) : (27) Describe date and nature of (include surgery) unknown none present X-RAY OR OTHER RADIATION: (other than routine chest and fracture diagnosis) unknown none present PELVIC DISEASE OR SURGERY: unknown none present OTHER SIGNIFICANT DISEASES: unknown none present positive findings. 0 1 2 (.28) 0 1 2 (29) 0 1 2 (30) 0 1 2 FAMILY HISTORY HEART DISEASE: unknown none present •(31) 0 1 2 Family includes the premature's, parents, grandparents, f u l l siblings, and parents' f u l l siblings 71 PRENATAL HISTORY FAMILY HISTORY COMMENTS CANCER: unknown none present (32) 0 1 2 TUBERCULOSIS: unknown none present (33) 0 1 2 DIABETES: unknown none present (34) 0 1 2 CONGENITAL ANOMALIES: (of distinct medico-social significance) unknown none present (35) 0 1 2 MULTIPLE PREGNANCY; unknown none present (36) 0 1 2 NEUROMUSCULAR AND PSYCHIATRIC DISORDERS: (37) unknown none epilepsy palsy retardation mental disorder -mental disorder -other (blindness. emotional psychotic deafness, speech 0 1 2 3 4 5 6 defect) OTHER SIGNIFICANT DISEASES: unknown none present (38) 0 1 2 HISTORY OF PRESENT PREGNANCY AGE OF MOTHER AT DELIVERY: unknown less than 15 years 15 to 19 years 20 to 24 years 25 to 29 years 30 to 34 years (39) 0 1 2 3 4 5 Describe any unusual findings, PRENATAL RECORD HISTORY OF PRESENT PREGNANCY COMMENTS 35 to 39 years 6 40 or more years 7 HOSPITALIZATION DURING PREGNANCY: (40) unknown 0 none 1 present 2 PRENATAL CARE: (41) unknown 0 none 1 private MD from 1st trimester 2 private MD from 2nd trimester 3 private MD from 3rd trimester 4 staff clinic from 1st trimester 5 staff clinic from 2nd trimester 6 staff clinic from 3rd trimester 7 MARITAL STATUS: (42) unknown 0 single 1 married 2 separated 3 divorced 4 common-law 5 married, not to father of child 6 widowed 7 other 8 BLOOD GROUP OF MOTHER: unknown 0 Rh positive A Rh positive B Rh positive AB Rh positive 0 Rh negative A Rh negative B Rh negative AB Rh negative only partly known SEROLOGY OF MOTHER: unknown negative positive RADIATION OF MOTHER: (other than routine chest or fracture diagnosis). unknown none 1st trimester only (43) 0 1 2 3 4 5 6 7 (44) 0 1 2 (45) 0 1 2 PRENATAL RECORD HISTORY OF PRESENT PREGNANCY 2nd trimester only 3rd trimester only more than one trimester ILLNESS DURING PREGNANCY: (other than complications of pregnancy listed below) unknown none 1st trimester only 2nd trimester only 3rd trimester only more than one trimester EMPLOYMENT DURING PREGNANCY: (beyond the 1st trimester) unknown housewife only paid work outside household-sedentary paid work outside household-non-sedentary other NUTRITION DURING PREGNANCY: (subjective impression) unknown probably adequate diet probably inadequate diet CIGARETTE SMOKING HABITS: unknown never smoked used to smoke but stopped before pregnancy smoked during pregnancy CIGARETTE SMOKING HABITS: unknown none listed below smoked during pregnancy: -# of cigarettes per day at beginning of pregnancy less than 10/day 10 to 20/day more than 20/day CIGARETTE SMOKING HABITS: unknown none listed below smoked during pregnancy: -# of cigarettes COMMENTS 3 4 5 (.46) 0 1 2 3 4 5 (47) 0 1 2 3 4 (48) 0 1 2 (49) 0 1 2 3 (50) 0 1 2 3 4 (51) 0 1 74 PRENATAL RECORD HISTORY OF PRESENT PREGNANCY per day at end of pregnancy less than 10/day 2 10 to 20/day 3 more than 20/day 4 MEDICATIONS DURING PREGNANCY Please place the appropriate number in the following columns (52-59). unknown 0 not used....1 used 2 SEDATIVES AND HYPONOTICS : (.52) TRANQUILIZERS, ANTIDEPRESSANTS, & ANTHIHISTAMINES: (53) DIURETICS AND HYPOTENSIVES: (54) ANTIBIOTICS AND SULFONAMIDES: (55) IMMUNIZATIONS AND VACCINES: (56) STEROIDS AND ENDOCRINE PREPARATIONS: (57) POTENTIAL ABORTIFACIENTS: (58) OTHER MEDICATIONS: (59) COMPLICATIONS OF PREGNANCY COMMENTS HYPEREMESIS (more than morning vomiting in the first 3 months) (60) unknown 0 none 1 present 2 TOXAEMIA: (61) unknown 0 none 1 pre-eclampsia 2 eclampsia - antepartum 3 eclampsia - intrapartum 4 eclampsia - postpartum 5 essential hypertension 6 other 7 HAEMORRHAGE (Antepartum Only): (62) unknown 0 none 1 placenta praevia 2 abruptio placentae 3 other antepartum vaginal bleeding 4 Pre-eclampsia defined as one or more of the following: hypertension over 140/90 proteinuria Eclampsia defined as above plus convulsions or coma. 75 PRENATAL RECORD COMMENTS COMPLICATIONS OF PREGNANCY URINARY TRACT INFECTION: unknown none present (63) 0 1 2 PELVIC DISEASE: unknown none present (64) 0 1 2 AMNIOTIC FLUID (Abnormal Volume): (65) unknown 0 no abnormality 1 oligohydramnios 2 polyhydramnios 3 ANAEMIA: (66) unknown 0 none 1 present 2 Polyhydramnios defined c l i n i -cally as unusual uterine enlargement with: a) difficulty in palpation of fetal small parts. b) difficulty in hearing fetal heart tones. c) easy ballottement of fetus d) more than 2 litres of measured amniotic fluid. EXCESS WEIGHT GAIN: unknown none present (67) 0 1 2 NEUROPSYCHIATRY DISORDERS: unknown none epilepsy palsy retardation mental illness - emotional mental illness - psychotic other (68) 0 1 2 3 4 5 6 7 HEART DISEASE (DURING PREGNANCY): (69) unknown 0 none 1 present 2 OTHER SIGNIFICANT DISEASE COMPLICATIONS OF PREGNANCY: (70) unknown 0 none 1 present 2 76 Appendix B U.B.C. LABOUR & DELIVERY RECORD UNIVERSITY OF BRITISH COLUMBIA DEPARTMENT OF PAEDIATRICS PREMATURE GROWTH AND DEVELOPMENT SURVEY 77 LABOUR AND DELIVERY CASE NUMBER: (1) (2) (3) BIRTHDATE OF PREMATURE: (4) (5) (6) (7) (8) (9) GESTATIONAL AGE: unknown known (10) (11) ONSET OF LABOUR: (12) unknown 0 spontaneous 1 f a l l , injury or accident 2 accompanying illness 3 self induced (specify) 4 medically induced (specify) 5 surgically induced 6 other 7 DURATION OF LABOUR (FIRST STAGE) : (.13) unknown 0 less than 2 hours 1 2 to 12 hours 2 13 to 24 hours 3 25 to 48 hours 4 49 or mo.re hours 5 DURATION OF LABOUR (SECOND STAGE): (14) unknown 0 less than 15 minutes 1 15 to 30 minutes 2 31 to 60 minutes 3 1 to 6 hours 4 7 to 12 hours 5 13 to 24 hours 6 more than 24 hours 7 DURATION OF LABOUR (TOTAL STAGE I & II) unknown 0 precipitate 1 more than 3 hours and up to 6 hours 2 7 to 12 hours 3 13 to 24 hours 4 25 to 48 hours 5 49 or more hours 6 (15) NAME OF CHILD: NAME OF MOTHER: HISTORY TAKEN BY: SOURCES(S) OF MATERIAL: DATE OF HISTORY: COMMENTS To calculate gestational age, count weeks on calendar from first day of last menstrual period. L.M.P.: E.D.C.: To calculate E.D.C, add 40 weeks to L.M.P. As specified in V.G.H. Labour Record Precipitate is 3 hours or less than total labour 78 LABOUR AND DELIVERY MEDICATIONS DURING LABOUR (excluding medical induction) Please place the appropriate number in the following columns (16-28). unknown 0 not used 1 used 2 BARBITURATES: (16) DEMERAOL: (17) TRANQUILIZERS AND ANTIHISTAMINES: (18) MORPHINE AND HEROIN: (.19) SCOPOLAMINE: (20) TRILENE AS AN ANALGESIC: (.21) NITROUS OXIDE AS AN ANALGESIC: (22) I.V. GLUCOSE: (.23) OXYGEN: (24) MAGNESIUM SULFATE & ANTIHYPERTENSIVES: (.25) ANTIBOTICS AND SULFONAMINES: (26) VITAMINE K: ' (.27) OTHER MEDICATIONS NOT LISTED ABOVE: (.28) COMPLICATIONS OF LABOUR COMMENTS Detail drug, time prior PREMATURE RUPTURE OF MEMBRANES: (29) unknown 0 none 1 present 2 UTERINE INERTIA: (30) unknown 0 none 1 present 2 PROLONGED LABOUR: (31) unknown 0 none 1 present 2 Defined as more than 12 hours before labour commenced. Defined as more than 24 hours altogether for Stage I & II - i.e. from beginning of labour to birth of infant. DISPROPORTION: (32) LABOUR AND DELIVERY 79 COMPLICATIONS OF LABOUR COMMENTS unknown none present 0 1 2 ANTEPARTUM HAEMORRHAGE: unknown none present TOXAEMIA: unknown none present - pre eclampsia present - eclampsia OTHER COMPLICATIONS: unknown none present (33) 0 1 2 (34) 0 1 2 3 (35) 0 1 2 See previous definitions DELIVERY PRESENTATION: unknown vertex full breech frank breech footling breech face or brow compound other (36) 0 1 2 3 4 5 6 7 DELIVERY: unknown spontaneous forceps assisted breech extracted breech external version manual or forceps rotation Caesarean Section other (37) 0 1 2 3 4 5 6 7 8 CORD COMPLICATIONS: unknown none present (38) 0 1 2 FOETAL DISTRESS: unknown none present (39) 0 1 2 Defined by: passage of meconium, foetal heart rate less than 100 per minute. 80 LABOUR AND DELIVERY DELIVERY COMMENTS EPISIOTOMY: unknown none present (40) 0 1 2 ANAESTHESIA (LOCAL): unknown none infiltration pudendal block epidural or peridural spinal other (41) 0 1 2 3 4 5 6 Detail agent, dose, duration use, and amount of oxygen ANAESTHESIA (GENERAL): unknown none intermittent inhalation continuous inhalation intravenous other (42) 0 1 2 3 4 PLACENTA: (43) unknown 0 no gross abnormality 1 abnormal 2 RESUSCITATION: (44) unknown 0 none 1 gastric suction 2 tracheal suction 3 open oxygen 4 positive pressure oxygen or air 5 tracheal intubation 6 drugs 7 other 8 APGAR SCORE: (45) (46) (47) State minutes after unknown X X X scores recorded. zero 0 0 0 one 1 1 1 (45) two 2 2 2 three 3 3 3 (46) .. four 4 4 4 five 5 5 5 (47) .. six 6 6 6 seven 7 7 7 eight 8 8 8 nine or ten 9 9 9 LABOUR AND DELIVERY DELIVERY COMMENTS BIRTH WEIGHT: (48) unknown 0 under 2 lb. 8 oz. 1 2 lb. 9 oz. to 3 lb. 2 3 lb. 1 oz. to 3 lb. 8 oz. 3 3 lb. 9 oz. to 4 lb. 4 4 lb. 1 oz. to 4 lb. 8 oz. 5 4 lb..9 oz. or more PLURALITY: (49) unknown 0 single 1 twin birth 2 triplet birth 3 other 4 RACE AND SEX: (50) unknown 0 white male 1 oriental male 2 North American Indian male 3 negro male 4 white female 5 oriental female 6 North American Indian female 7 negro female ' 8 other 9 82 TESTS AND PROCEDURES CORD BLOOD COMMENTS ABO BLOOD TYPE: unknown 0 A B AB other Rh BLOOD TYPE: unknown positive negative COOMBS: unknown negative positive TOTAL BILIRUBIN: unknown less than 3 mg % 3 to 419 mg % 5 mg % or more HEMOGLOBIN: unknown less than 6 mg % 6 to 7.9 mg % 8 to 9.9 mg % 10 to 11.9 mg % 12 to 13.9 mg % 14 to 15.9 mg % 16 to 17.9 mg % 18 to 19.9 mg % 20 mg % or more VDRL: unknown negative positive NOT CORD BLOOD MINIMUM AND MAXIMUN HEMOGLOBIN: unknown less than 6 gm % 6 to 7.9 gm % 8 to 9.9 gm % 10 to 11.9 gm % 12 to 13.9 gm % (51) 0 1 2 3 4 5 (52) 0 1 2 (53) 0 1 2 (54) 0 1 2 3 (55) 0 1 2 3 4 5 6 7 8 9 (56) 0 1 ? Min. Max. (57) (58) 0 0 State whether Coombs direct or indirect test used. For indirect Coombs, specify type of adult cells used. 1 2 3 4 5 1 2 3 4 5 Use separate worksheet overleaf to record running record of laboratory tests. Summarize on this sheet after hospital discharge. 83 14 to 15.9 gm % 6 6 16 to 17.9 gm % 7 7 18 to 19.9 gm % 8 8 20 gm % or more 9 9 TYPE OF BLOOD USED FOR HEMOGLOBIN Min. Max. (59) (60) unknown 0 0 capillary (prick) 1 1 venous 2 2 MAXIMUM TOTAL SERUM BILIRUBIN: (61) unknown 0 less than 1 mg % 1 1 to 5.9 mg % 2 6 to 10.9 mg % 3 11 to 15.9 mg % 4 16 to 20.9 mg % 5 21 to 25.9 mg % 6 26 to 29.9 mg % 7 30 mg % or more 8 TYPE OF BLOOD USED FOR BILIRUBIN ABOVE: (62) unknown 0 capillary (prick) 1 venous 2 BACTERIOLOGY: (63) unknown 0 cultures negative for pathogens 1 cultures positive for pathogens 2 BLOOD CHEMISTRY: (64) unknown 0 known - normal 1 known - abnormal 2 FURTHER HEMATOLOGY: (65) unknown 0 known - normal 1 known - abnormal 2 OTHER TESTS AND PROCEDURES: (67) unknown 0 known - normal 1 known - abnormal 2 CSF: (66) unknown 0 known - normal 1 known - abnormal 2 Specify: origin of culture organisms present sensitivity Specify: tests used results CARD INDENTIFICATION (79) (80) 84 Appendix C U.B.C. NURSERY HISTORY RECORD 85 UNIVERSITY OF BRITISH COLUMBIA DEPARTMENT OF PAEDIATRICS PREMATURE GROWTH AND DEVELOPMENT SURVEY NURSERY HISTORY CASE NUMBER (1) (2) (3) BIRTHDATE OF PREMATURE: DATE MONTH YEAR (4) (5) C6) (7) (8) (9) CODING: For each item either 1. circle -unknown, or f i l l in appropriate digits boxes (e.g. #(10) (11)) for 2. Circle appropriate number (e.g. under (14)). • x i f in the INSTRUCTIONS: Use this side to record events in history. Do not f i l l out left (coded) side until baby is discharged, (i.e. left side is for summary of positive findings only) . NAME OF CHILD: EXAMINER - E; DATE - D; STATUS - S; TIME - T: NUMBER OF DAYS INCUBATED (10) unknown known NUMBER OF DAYS IN HOSPITAL: (12) unknown known (11) COMMENTS Isolette - I; Armstrong - A; (13) Crib - C: OXYGEN CONCENTRATION: (14) unknown 0 none added 1 less than 30% maximum 2 30% to 40% maximum 3 40.1% or more maximum 4 DURATION OF OXYGEN THERAPY: (15) unknown 0 none added 1 fir s t 24 hours only 2 first 48 hours only 3 more than 48 hours 4 TEMPERATURE OF INCUBATOR: (16) unknown 0 less than 80 degrees F 1 80 to 84 degrees F 2 85 to 90 degrees F 3 more than 90 degress F 4 BABY'S RECTAL TEMP. ON NURSERY ADMISSION: (17) unknown 0 below 94 degrees F 1 94 to 96 degrees F 2 96.1 degrees F or more 3 BABY'S RECTAL TEMP. AFTER ADMISSION: (18) NURSERY HISTORY unknown i.O below 96 degrees F 1 a l l between 96.1 and 99.9 degrees F 2 above 99.9 degrees F 3 MINIMUM WEIGHT: POUNDS OUNCES (19) : (20) (21) unknown known AGE WHEN ORAL FEEDINGS STARTED: (22) unknown 0 less than 24 hours 1 25 to 48 hours 2 after 48 hours 3 ORAL FEEDING METHODS: (23) unknown 0 gavage i n i t i a l l y with bottle later/ 1 bottle from the start; no gavage required 2 gavage i n i t i a l l y with breast later 3 breast from the start; no gavage 4 other 5 TYPE OF MILK: (24) unknown 0 breast 1 evaporated 2 dried (specify) 3 other 4 ' BABY'S ACTIVITY: (25) unknown 0 normal amount 1 excessive amount 2 less than normal amount 3 BABY'S CRY: (26) unknown 0 no rmal 1 excessive 2 poor 3 RESPIRATORY ABNORMALITIES: (27) unknown 0 none 1 apnoea 2 grunting 3 retraction 4 other 5 PALLOR: unknown (2:8) 0 NURSERY HISTORY absent present CYANOSIS: unknown absent peripheral only general BLEEDING: unknown absent present SEIZURES: unknown absent present TWITCHING: unknown absent present OEDEMA: unknown absent present JAUNDICE: unknown absent present at birth present before 48 hours old present 49 to 72 hours old present 73 to 96 hours old present after 4 days old VOMITING: unknown absent present FEEDING PROBLEM: unknown absent present MEDICATIONS: unknown none antibiotics (specify) vitamin K COMMENTS 1 2 (29) 0 1 2 3 (30) 0 1 2 (31) 0 1 2 (32) 0 1 2 (33) 0 1 2 (34) 0 1 2 3 4 5 6 (35) 0 1 2 (36) 0 1 n (37) 0 1 2 3 NURSERY HISTORY other vitamins iron preparation other (specify) PROCEDURES: unknown none parenteral fluid exchange transfusion other blood transfusion other (specify) OTHER ABNORMALITIES NOTED: unknown absent present COMMENTS 4 5 6 (38) 0 1 2 3 4 5 (39) 0 1 2 89 Appendix D U.B.C. NEONATAL EXAMINATION UNIVERSITY OF BRITISH COLUMBIA DEPARTMENT OF PAEDIATRICS PREMATURE GROWTH AND DEVELOPMENT SURVEY 90 NEONATAL EXAMINATION CASE NUMBER (1) (2) (3) BIRTHDATE OF PREMATURE: DATE: MONTH YEAR (4) (5) (6) (7) (8) (9) CODING: For each item either 1. circle - x i f unknown, or f i l l in appropriate digits in boxes, (e.g. #(10) (11)) or 2. Circle the appropriate number (e.g. under (18). Code earliest recorded measurements in centimeters. INSTRUCTIONS: Use this side to record exam results. Do not f i l l out left (coded) side until baby is discharged i.e. left side is for summary of positive findings only) NAME OF CHILD: BODY LENGTH: unknown known (10) (11) EXAMINER - E; STATUS - S; DATE - D; TIME - T; COMMENTS CROWN RUMP LENGTH (12) (13) unknown known CHEST CIRCUMFERENCE: (16) (17) unknown known CYANOSIS: (18) unknown 0 absent 1 peripheral only 2 general 3 JAUNDICE: (19) unknown 0 absent 1 present 2 SUBCUTANEOUS TISSUE: (20) unknown 0 oedema 1 dehydration 2 normal 3 other 4 SKIN APPEARANCE AND COLOUR: unknown normal parchment or pallor rash petechiae or ecchymosis inflammation sclerema (21) 0 1 2 3 4 5 5 NEONATAL EXAMINATION staining o th er FACIES: unknown normal asymmetrical other HEAD: unknown normal separated sutures moulding cephalhematoma other FONTANELLE SIZE ANTERIOR A.P.: unknown known ANTERIOR TRANSVERSE: unknown known POSTERIOR A.P.: unknown known POSTERIOR TRANSVERSE: unknown known TENSION OF FONTANELLES: unknown no rmal other EARS: unknown normal other NOSE: unknown normal other MOUTH AND PHARYNX: unknown normal 7 COMMENTS 8 (22) 0 1 2 3 (23) 0 1 2 3 4 5 (24) 0 1 (.25) 0 1 (26) 0 1 (27) 0 1 (28) 0 1 2 (29) 0 1 2 (30) 0 1 2 (31) 0 1 NEONATAL EXAMINATION other COMMENTS 2 NECK: (32) unknown 0 normal 1 other 2 THORAX: (33) unknown 0 normal 1 other 2 RESPIRATIONS: (34) unknown 0 normal 1 irregular 2 shallow 1 3 grunting 4 laboured 5 retracted 6 disorganized 7 altered breath sounds 8 other 9 HEART: (35) unknown 0 normal 1 tachycardia (more than 180) 2 brachycardia (less than 100) 3 irregular rhythms 4 murmur 5 t h r i l l 6 other 7 FEMORAL PULSES: (36) unknown 0 strong and equal bilaterally 1 weak or asymmetrical 2 ABDOMEN: (37) unknown 0 normal 1 distention 2 abnormal liver 3 abnormal spleen 4 abnormal kidney 5 other 6 GENITALIA: (38) unknown 0 normal 1 abnormal female 2 abnormal male 3 NEONATAL EXAMINATION COMMENTS undetermined 4 SPINE: (39) unknown 0 normal 1 other 2 EXTREMITIES AND JOINTS (40) unknown 0 normal 1 other 2 SUCK: (evaluate with finger) (41) unknown 0 present 1 weak 2 absent 3 PALMAR GRASP: (42) unknown 0 present 1 asymmetrical 2 absent 3 PLANTAR GRASP: (43) unknown 0 present 1 asymmetrical 2 MORO RESPONSE: (44) unknown 0 obtained with ease 1 obtained with difficulty 2 no constant pattern 3 no response 4 MORO RESPONSE OF ARMS: (45) unknown 0 normal 1 flexor component absent with anterior 2 extension flexor component absent with lateral extension 3 asymmetrical 4 other 5 MORO RESPONSE OF LEGS: (46) unknown 0 movement 1 no movement 2 CRY: (47) unknown 0 normal 1 94 NEONATAL EXAMINATION COMMENTS none other MOTOR ACTIVITY: unknown normal tremulous or jittery rapid jerky movements myoclonic movements writhing movements asymmetrical movements local convulsions general convulsions other (48) 0 1 2 3 4 5 6 7 8 9 TONE Please place the appropriate number in the following colums (49-53): unknown 0 hypotonic 1 questionably hypotonic 2 normal 3 questionably hypertonic.....4 hypertonic 5 assymmetrical 6 TONE OF UPPER EXTREMITIES: (49) TONE OF LOWER EXTREMITIES: (50) TONE OF NECK FLEXOR: (51) TONE OF NECK EXTENSOR: (52) TONE OF TRUNK: (53) CLINICAL IMPRESSION: (54) unknown 0 normal 1 central nervous system defect or injury 2 congenital malformations (other than CNS) 3 other 4 UNSATISFACTORY EXAM CONDITIONS: (.55) unknown 0 absent 1 present 2 EYES: (Infected) (56) unknown 0 absent 1 present 2 95 Appendix E U.B.C. NEONATAL NEUROLOGICAL EXAMINATION 96 UNIVERSITY OF BRITISH COLUMBIA DEPARTMENT OF PAEDIATRICS PREMATURE GROWTH AND DEVELOPMENT SURVEY NEONATAL NEUROLOGICAL EXAMINATION CASE NUMBER: (1) (2) (3) BIRTHDATE OF PREMATURE: DATE: MONTH:, YEAR: (4) (5) (6) (7) (8) (9) AGE AT EXAM (DAYS): (10) (11) CODING: For each item either 1. f i l l in appropriate digits in boxes or 2. circle the appropriate number. SPONTANEOUS MOVEMENTS EYES - POSITION AT REST: unknown central position one position two position three position four unable to evaluate R. L. (12) (13) 0 1 2 3 4 5 6 0 1 2 3 4 5 6 NAME OF CHILD: NAME OF EXAMINER: STATUS OF EXAMINER: DATE OF EXAM: TIME OF EXAM: TIME SINCE LAST FEED: , COMMENTS Describe any abnormal findings, R. L. MOVEMENTS OF FACE: (14) unknown 0 present and symmetrical 1 absent or diminished, symmetrical 2 asymmetrical 3 other 4 PALPEBRAL FISSURES: (15) unknown 0 equal 1 unequal 2 EYES - STARING: (16) unknown 0 absent 1 present 2 POSTURE: (17) unknown 0 no rmal 1 abnormal - opisthotonus 2 abnormal - head retraction 3 unusual position of arms 4 unusual position of legs 5 other 6 NEONATAL NEUROLOGICAL EXAMINATION SPONTANEOUS MOVEMENTS MOTOR ACTIVITY: (18) unknown 0 normal 1 tremulous or jittery 2 jerky or myoclonic movements 3 writhing movements 4 asymmetrical movements 5 local convulsions 6 general convulsions 7 other 8 MOVEMENTS OF ARMS: (19) unknown 0 normal 1 questionable abnormality 2 abnormal 3 MOVEMENTS OF LEGS: (20) unknown 0 normal 1 questionable abnormality 2 abnormal 3 RESPONSES TO STIMULI CRY (QUALITY): (21) unknown 0 normal 1 questionable abnormality 2 abnormal 3 not heard 4 BLINK REFLEX: (22) unknown 0 present and symmetrical 1 questionable response symmetrically 2 absent bilaterally 3 asymmetrical response 4 other 5 CILIARY REFLEX: R. L. (23) (24) unknown 0 0 both eyes closed 1 1 only stimulated eye closed 2 2 no response 3 3 other 4 4 AUDITORY RESPONSE: (25) unknown 0 present 1 asymmetrical 2 unable to evaluate 3 NEONATAL NEUROLOGICAL EXAMINATION RESPONSES TO STIMULI PALMAR GRASP: (26) unknown 0 present, symmetrical and consistent 1 present, symmetrical but not consistent 2 absent bilaterally 3 asymmetrical response 4 PLANTAR GRASP: (27) unknown 0 symmetrical response 1 absent bilaterally 2 asymetrical response 3 other 4 PATELLA JERK: (28) unknown 0 symmetrical response 1 absent bilaterally 2 asymmetrical response 3 other 4 ANKLE CLONUS: R. L. (29) (30) unknown 0 0 none 1 1 less than 8 beats 2 2 8 beats or more 3 3 SUCK: (31) unknown 0 strong 1 weak 2 absent 3 ROOTING RESPONSE: (32) unknown 0 movement toward stimulation 1 no movement 2 asymmetrical response 3 other 4 PRONE POSITION: (33) unknown 0 normal (a) l i f t s chin, turns head, makes crawling movements 1 normal (b) turns head and crawls, no chin up 2 questionable abnormality 3 abnormal 4 other 5 99 NEONATAL NEUROLOGICAL EXAMINATION MAXIMAL HANDLING OR STIMULATION EYE MOVEMENTS: unknown normal abnormal SETTING SUN SIGN unknown pupils remain central "setting sun" downward movement of eyes asymmetrical other LABYRINTHINE REFLEX Response during unknown no eye movement deviation to R. deviation to L. deviation to R. deviation to R. deviation to L. deviation to L. COMMENTS Rotate to -r rotation; without nystagmus without nystagmus with nystagmus to R with nystagmus to L with nystagmus to R with nystagmus to L LABYRINTHINE REFLEX: Response after rotation stopped unknown no eye movement deviation to R deviation to L deviation to R deviation to R L L deviation to deviation to without nystagmus without nystagmus with nystagmus to R with nystagmus to L with nystagmus to R with nystagmus to L, TONIC NECK REFLEX: EXTENSION: unknown jaw arm jaw leg occiput arm occiput leg absent Head to the -R. (36) 0 1 2 3 . 4 . 5 . 6 . 7 R. (38) 0 1 2 3 4 5 6 7 R. (40) 0 1 2 3 4 5 (34) 0 1 2 (35) 0 1 2 3 4 L. (37) 0 1 2 3 4 5 6 7 L. (39) 0 1 2 3 4 5 6 7 L. (41) 0 1 2 3 4 5 FLEXION: unknown jaw arm jaw leg occiput arm occiput leg absent R. L. (42) (43) 0 0 1 1 2 2 3 3 4 4 5 5 100 NEONATAL NEUROLOGICAL EXAMINATION MAXIMAL HANDLING OR STIMULATION COMMENTS RESPONSE TO TONIC NECK REFLEX: (44) unknown 0 obtained with ease 1 obtained with difficulty 2 no constant pattern 3 no response 4 TRACTION RESPONSE (45) unknown 0 normal - neck flexes, head controlled, and shoulder muscles assist 1 questionable abnormality 2 abnormal - no head control 3 abnormal - no neck flexion 4 abnormal - no shoulder assistance 4 WITHDRAWAL FROM PINPRICK TO SOLE: (46) unknown 0 withdrawal of stimulated extremity 1 elicited bilaterally 2 no response bilaterally 3 asymmetrical 4 other 5 INCURVATION OF TRUNK: (47) unknown 0 normal and symmetrical 1 questionable response 2 absent bilaterally 3 asymmetrical 4 other 5 STEPPING: (48) unknown 0 present, bilateral, symmetrical 1 questionable response 2 absent bilaterally 3 asymmetrical 4 other 5 PLACING: (49) unknown 0 present, bilateral, symmetrical 1 questionable response 2 absent bilaterally 3 asymmetrical 4 other 5 MORO RESPONSE: (50) unknown 0 obtained with ease 1 obtained with difficulty 2 no constant pattern 3 10.1 NEONATAL NEUROLOGICAL EXAMINATION MAXIMAL HANDLING OR STIMULATION COMMENTS MORO - RESPONSE OF ARMS: (52) unknown 0 normal - extensor and flexor components symmetrically present 1 flexor component absent with anterior extension 2 flexor component with lateral extension 3 asymmetrical 4 other 5 TONE Place the appropriate digit in the following colums (53-59). unknown 0 flaccid 1 hypotonic .... 2 normal 3 hypertonic ... 4 spastic 5 TONE OF ARMS: TONE OF LEGS: TONE OF NECK FLEXOR TONE OF NECK EXTENSOR TONE OF TRUNK: TRANSILLUMINATION: unknown absent - normal doubtful or questionable present unable to evaluate R. (53) R. (55) L. (54) L. (56) (57) (58) (59) (60) 0 1 2 3 4 COLLIS TEST: R. leg response L. leg stimulated unknown 0 flexion and abduction 1 flexion without abduc-tion 2 remaining in extension 3 other 4 L. leg response R. leg stimulated 0 1 2 3 4 ( l i f t infant's leg and but-tock by the ankle) 102 NEONATAL NEUROLOGICAL EXAMINATION COMMENTS MAXIMAL HANDLING OR STIMULATION CROSSED EXTENSION: unknown flexes and extends adduction with extension of toes flexes and extends without adduction flexes and extends without extending toes flexes without extension remains extended other R. leg response L. foot rubbed (63) 0 4 5 6 L. leg response R. foot rubbed (64) 0 1 2 PUPILS DIRECT REACTION TO LIGHT: unknown present and rapid bilaterally present but sluggish bilaterally absent bilaterally asymmetrical unable to evaluate EYES - EXTERNAL EXAMINATION: unknown normal hemorrhage other scleral or conjunc-tival (65) 0 1 2 3 4 5 (66) 0 1 2 3 (hold one leg in extension and rub sole of foot) 4 5 6 OPTHALMOSCOPIC EXAMINATION: unknown normal hemorrhage - retinal other unable to evaluate (67) NAME OF EXAMINER:.. 0 STATUS OF EXAMINER. 2 2 DATE OF EXAM 3 4 EEG: unknown normal borderline abnormal inadequate (68) 0 1 2 3 4 103 NEONATAL NEUROLOGICAL EXAMINATION COMMENTS MAXIMAL HANDLING OR STIMULATION EEG ABNORMALITIES: (70) unknown 0 none listed below 1 excess high voltage slow activity 2 excess high voltage fast activity 3 EEG ABNORMALITIES: (71) unknown 0 none listed below 1 paroxysmal features 2 spike 3 spike waves 4 other 5 IMPRESSION NEUROLOGICAL ABNORMALITIES: (72) unknown 0 none 1 suspicious but indefinite 2 definitely abnormal 3 NON-NEUROLOGICAL ABNORMALITIES: (73) unknown 0 none 1 minor abnormalities or diviations (no significant handicap) 2 questionable abnormalities 3 dp^inite major abnormalities 4 UNSATISFACTORY CONDITIONS FOR EXAMINATION: unknown absent present (74) 0 1 2 CARD IDENTIFICATION: (79) (80) 104 Appendix F U.B.C. HANDEDNESS SCALE 6% YEAR EXAMINATION 105 UNIVERSITY OF DEPARTMENT PREMATURES' GROWTH 6% YEAR BRITISH COLUMBIA OF PAEDIATRICS AND DEVELOPMENT SURVEY EXAMINATION HANDEDNESS: (61) unknown 0 variable 1 strong right-handedness 2 strong left-handedness 3 slight preference for right 4 slight preference for left 5 ambidextrous 6 other 7 Specify age at which handedness apparent (if known) Tests for handedness: 1) draw/write with a pencil 2) throw a ball 3) turn a door knob 4) cut with scissors 5) wind a watch Strong handedness means 4 or a l l of these done with same hand. 

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