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Normative penile anthropometry in term newborns in Kumasi, Ghana: a cross-sectional prospective study Asafo-Agyei, Serwah B; Ameyaw, Emmanuel; Chanoine, Jean-Pierre; Nguah, Samuel B Jan 26, 2017

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RESEARCH Open AccessNormative penile anthropometry in termnewborns in Kumasi, Ghana: a cross-sectional prospective studySerwah Bonsu Asafo-Agyei1*, Emmanuel Ameyaw1, Jean-Pierre Chanoine2 and Samuel Blay Nguah1AbstractBackground: Genital measurements are a useful adjunct in the early detection of various endocrine conditionsincluding hypopituitarism and disorders of sexual differentiation. Standards for genital sizes have been publishedbut racial/ethnic differences exist. This study was done to establish norms for genital sizes in term Ghanaian malenewborns.Methods: This was a cross-sectional study of all apparently well full-term newborns of postnatal age < 48 hand birth weight between 2.5 and 4.0 kg delivered at Komfo Anokye Teaching Hospital within the study period.Anthropometric and genital parameters were documented for study subjects as well as parental socio-demographic indices.Results: A total of 644 male newborns were recruited between May and September 2014. The mean penilelength (MPL) was 3.3 ± 0.5 cm and the mean penile width (MPW) was 1.05 ± 0.1 cm. An inverse relationshipwas found between maternal age and MPL (correlation coefficient −0.062, 95% CI −0.121 to −0.002; p = 0.04).MPL was also significantly different (p = 0.04) by mode of delivery, with babies delivered by caesarean sectionhaving the lowest MPL. MPL correlated positively with both gestational age (p = 0.04) and birth length (p < 0.001),while MPW correlated proportionally with birth weight and length (p < 0.001 for both).Conclusions: Using the conventional definition of micropenis as stretched penile length (SPL) < 2.5 standard deviation(SD) below the mean and macropenis as an SPL > 2.5 SD, a Ghanaian term newborn may warrant investigation if hehas an MPL < 2.1 cm or > 4.4 cm.Keywords: Penile length, Penile width, Genital size, Ghana, Micropenis, MacropenisBackgroundPenile size is a reflection of the adequacy of exposureof the male fetus to androgens, right from hypothal-amic/pituitary gonadotropins down to testicular andro-gens. Normative standards of penile sizes are thususeful for the diagnosis of genital/endocrine abnormal-ities [1]. Penile length abnormalities consist of micrope-nis and macropenis (‘large penis’). A micropenis is anabnormally small penis with a normal configuration [2].Conventionally, micropenis has been defined as astretched penile length (SPL) < 2.5 standard deviation(SD) below the mean for age with normal function andstructure. Likewise, an SPL > 2.5 SD is considered as amacropenis [2, 3].Micropenis is an important sign in neonates, since itmay be the only clue to the diagnosis of hypopituitarism,a potentially lethal but treatable condition [4]. It mayalso raise the clinical suspicion concerning the possibilityof associated hypoglycaemia, a life-threatening metabolicemergency associated with hypopituitarism or isolatedgrowth hormone deficiency [5]. Micropenis may alsoreflect an impairment specific to the hypothalamo-pituitary-gonadal axis, including isolated hypogonadism,poorly functioning, dysgenetic testicular tissue with ma-lignant potential or partial androgen insensitivity [6, 7].Early diagnosis of micropenis is important, because it* Correspondence: sbasafoagyei@gmail.com1Department of Child Health, Komfo Anokye Teaching Hospital, Kumasi,GhanaFull list of author information is available at the end of the article© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link tothe Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Asafo-Agyei et al. International Journal of Pediatric Endocrinology  (2017) 2017:2 DOI 10.1186/s13633-017-0042-1allows for various treatment options to be implementedearly [8].Conversely, a possibly large penis with hyperpigmenta-tion of the scrotum alerts the physician to the possibilityof congenital adrenal hyperplasia (CAH), a conditionthat can be fatal if not identified [9]. This is especiallycrucial in resource limited settings where newbornscreening for CAH is not routinely done, as newbornmales with CAH usually don’t have other signs of andro-gen excess and often die undiagnosed from salt wastingcrisis [10]. Macropenis has also been associated withrare syndromes like auriculo-condylar syndrome andcaudal dysplasia sequence [11, 12].Genital anthropometric measurements also help toavoid unwarranted investigations. It is useful in differen-tiating micropenis from an entirely normal ‘inconspicu-ous’ penis (concealed penis) [13].Normative genital anthropometric data for healthynewborns exist and were mainly derived from Caucasianand Asian infants [3, 6, 14–16]. However, this may notbe applicable to African infants. Indeed, previous studieshave reported racial/ethnic differences in newborn penilesizes [1, 17, 18]. Some studies have even demonstratedsignificant differences in the same ethnic group with thepassage of time and improvement in national economicconditions [19]. Recent studies from various parts of theworld have aimed at establishing genital anthropometricnorms representing their own populations [20–24]. Nosuch comparable published data exist for Ghana.Hence, this study aimed at establishing the referenceranges for penile sizes in apparently healthy termnewborns in Ghana.MethodsA cross-sectional prospective study of all apparently wellterm male newborns delivered at Komfo Anokye Teach-ing Hospital (KATH) was carried out from May 2014 toSeptember 2014. KATH is a tertiary teaching hospital inKumasi, the second largest city in Ghana. Kumasi is ametropolitan city but majority of its inhabitants areAkans of the Ashanti tribe.A nurse attached to the paediatric endocrine unit wastrained to assist the principal investigator with the geni-tal and anthropometric measurements. Two research as-sistants were trained to assist the two examiners withpositioning of the babies and data entry. All apparentlywell male term newborns with a gestational age of 40 ±2 weeks and birth weight between 2.5 and 4.0 kg wereincluded. An initial clinical assessment guided by ascreening form was done to find out which babies wereeligible. Newborns with major congenital anomalies/dysmorphism, genital anomalies, breech presentation atbirth, maternal pregnancy history of hormonal drug use,maternal signs of virilisation during pregnancy, maternalpre-eclampsia or diabetes were all excluded. For eligiblebabies, the study was explained to the parent(s) andwritten informed consent was sought for. The baby wasthen enrolled if the parent(s) consented. Recruitmentwas done within 48 h after delivery. A complete ante-natal history was obtained from the mother and fromthe hospital records, including a history of ingestion ofherbal medicine or prescribed medications. The gesta-tional age was determined by using the last menstrualperiod and early ultrasound results and confirmed if ne-cessary with Dubowitz/Ballard score [25]. The socio-economic status of the parents was determined usingthe Oyedeji classification [26]. A complete physicalexamination of each baby was done and anthropometricmeasurements taken. All anthropometric measurementswere done by a 2-member team, with one person takingthe measurements while the other positioned the babyand helped enter the data onto the Case report form.In a warm environment, the newborns were put in asupine position and the perineum was adequately ex-posed. The SPL was measured by holding the glans gen-tly between the thumb and forefinger and measuringfrom the pubic ramus, along the dorsum, to the tip ofthe glans penis with a disposable wooden spatula. Theshaft of the penis was stretched to the point of resistanceand the suprapubic fat pad compressed as completely aspossible. The foreskin was not included in the measure-ment. The tip of the glans was marked on the spatula by apencil. The distance between the tip of the spatula and themarked point was then measured with a measuring tape/ruler. The penile width was determined with a digital Ver-nier caliper (Resolution 0.01 mm, Accuracy +/−0.02 mm)by measuring the widest diameter along the shaft to thenearest 0.01 mm. All measurements were done twice andthe mean value recorded. Majority (72.1%) of the measure-ments was done by the principal investigator but fort-nightly, genital measurements were done on 5 randomlyselected babies by both examiners to evaluate for inter-observer variability, which remained insignificant through-out the study. The standard deviations for inter-observervariation were 0.04 cm and 0.13 mm and 95% of pairedmeasurements were within range of 0.09 cm and 0.26 mmfor penile length and penile width respectively.The data was analyzed using R statistical softwareversion 3.1.2. Continuous variables were summarizedand presented as means with standard deviation as wellas median with their corresponding ranges. Single cat-egorical variables were tabulated and expressed aspercentages. The relationships between the genital mea-surements and the various categorical variables weredetermined using an analysis of variance, correcting forpossible confounders and reporting the respective p-values as appropriate. Relationships between the genitalmeasurement and other continuous variables wereAsafo-Agyei et al. International Journal of Pediatric Endocrinology  (2017) 2017:2 Page 2 of 7however determined using linear regression. These ana-lyses were presented as their regression coefficient withtheir 95% confidence intervals. To establish the variouspercentiles for the genital measurements they were eachsummarized for gestational age to display the; 1st, 3rd,50th, 97th, and the 99th age specific percentiles with therange. For all analysis a two sided p-value of <0.05 wasconsidered statistically significant.The study was approved by the Committee on HumanResearch, Publications and Ethics of KATH/KwameNkrumah University of Science and Technology,Kumasi. The Heads of the Department of Child Healthand the Obstetrics and Gynaecology department as wellas other staff in both departments were briefed aboutthe study. A written Informed Consent Form detailingthe study purpose, benefit and possible risk of the studyto the children were provided and explained to the par-ent(s) in a language they could understand. The childwas only enrolled if the parent(s) consented.ResultsA total of 644 male infants were studied. A summarydata of study subjects is shown in Table 1. The distribu-tion of maternal tribe was Akan 451 (70%), Mole-Dagomba 92 (14.3%), Ewe 20 (3.1%), Ga-Adangbe 7(1.1%) and ‘Others’ (including Hausa, Grushie andWangara tribes) 74 (11.5%). Genital measurements fromstudy subjects were used to construct gestation-specificgenital anthropometry percentile charts (Table 2). Themean penile length (MPL) was 3.3 cm and the −2.5 SDand +2.5 SD for MPL were 2.1 cm and 4.4 cmrespectively.There was no significant difference in genital size bymaternal tribe, parental socioeconomic score or maternalherbal intake. Eighty-three mothers (12.9%) took herbs atvarying periods during their pregnancy. There was also nosignificant difference in genital measurements done in thefirst 24 h of postnatal life and those done from 24 h up to48 h. MPL, but not mean penile width (MPW), wasnegatively correlated with maternal age (CorrelationCoefficient −0.062, 95% CI −0.121 to −0.002; p = 0.04) butpositively correlated with gestational age (Correlation Co-efficient 0.33, 95% CI: 0.02–0.64, p-value = 0.04). In ananalysis of variance, only MPL was significantly differentby mode of delivery. A post hoc analysis found a differ-ence between only the caesarean section (C/S) group andthe spontaneous vaginal delivery (SVD) group (p = 0.038).Table 3 shows the correlation between genital size and an-thropometric parameters.DiscussionMicropenis result from a heterogenous group of disor-ders; the most common being fetal testosterone defi-ciency [18]. In the human male fetus, testosteronesynthesis by the fetal Leydig cell during the criticalperiod of male differentiation (8–12weeks) is under theinfluence of placental human chorionic gonadotrophin.After mid-gestation, fetal pituitary Luteinizing hormonemodulates fetal testosterone synthesis by the Leydig celland, consequently, affects the growth of the differenti-ated penis [7]. Growth hormone acting in conjunctionwith insulin-like growth factors may also modulate an-drogen action [27]. Thus, males with congenital hypo-pituitarism as well as isolated gonadotropin or growthTable 1 Summary data of study subjectsMean SD Median Minimum MaximumGestational age (weeks) 40.0 1.2 40.1 38.0 42.0Post-natal age (hours) 10.1 8.3 8.0 1 48Five Minute APGAR score 8.6 0.6 9.0 6 10Birth weight (kgs) 3.2 0.4 3.2 2.5 4.0Length (cm) 48.7 2.1 49.0 39.5 54.0Head Circumference (cm) 34.4 1.3 34.4 30.0 38.2Penile Length (cm) 3.3 0.5 3.2 2.0 4.8Penile Width(cm) 1.05 0.1 1.05 0.69 1.37Heart Rate (bpm) 134 11 136 96 164Respiratory Rate (cpm) 49 11 48 28 90Temperature (°C) 35.9 0.8 36 34.0 37.9Maternal age (years) 28.5 6.2 28.0 15 49Antenatal Care attendance 7 3 7 0 20Paternal Age (years) 34.7 7.4 34 18 65Parental socioeconomicscore3.3 1.0 3.5 1 5Table 2 Percentile chart for penile size by gestational age inmale newbornsGestationalage (weeks)PercentilesMin 1st 3rd 50th 97th 99th MaxPenile Length (cm)38 2.3 2.3 2.6 3.1 4.2 4.3 4.439 2.2 2.2 2.5 3.2 4.1 4.3 4.740 2.0 2.2 2.2 3.3 4.4 4.5 4.841 2.0 2.2 2.3 3.2 4.0 4.3 4.542 2.3 2.5 2.7 3.2 4.0 4.1 4.1Penile Width (mm)38 7.6 7.7 8.2 10.3 13.1 13.2 13.239 6.9 7.4 8.2 10.6 12.8 13.4 13.740 6.9 7.7 8.5 10.5 12.5 12.7 13.541 7.8 7.9 8.3 10.5 12.4 12.7 13.242 7.3 7.5 8.0 10.9 12.3 13.1 13.7Asafo-Agyei et al. International Journal of Pediatric Endocrinology  (2017) 2017:2 Page 3 of 7hormone deficiency can present with normal male differ-entiation and micropenis at birth. Rarely micropenis isassociated with 5 alpha reductase enzyme deficiency ormild defects in the androgen receptor [7], though pa-tients with 5 alpha reductase enzyme deficiency aremore likely to have associated hypospadias than onlyisolated micropenis [28].The main purpose of this study was to define norma-tive genital sizes in the Ghanaian male newborn. To thebest of our knowledge, this is the first published study ofpenile size in Ghanaian newborns. The relatively largersample size allowed for a more precise construction ofgestational specific percentile charts than in previouslypublished smaller scale studies. Studies done in differentparts of the world have reported varying MPL in new-borns ranging from 2.35 to 3.77 cm [3, 14–16, 20, 29,30]. This study found an MPL of 3.3 ± 0.5 cm. Using theconventional definition of micropenis as SPL < 2.5 SDbelow the mean and ‘macropenis’ as an SPL > 2.5 SD, aGhanaian term newborn may warrant investigation if hehas an MPL < 2.1 cm or > 4.4 cm.Among studies with similar methodology, Akin et al.[21] reported a relatively lower MPL of 3.16 ± 0.39 cm inTurkey and Semiz et al. [30] also reported an even lowerMPL of 2.81 ± 0.32 cm in 746 term Turkish newborns.Possible factors accounting for this observed differenceare inter-observer variation and differences in the char-acteristics of the study populations including ethnicity/race [17]. Reports from other parts of Asia have alsobeen relatively lower [23, 31], though not uniformly so[18, 22, 32]. Very low SPL have especially been reportedin Indonesian newborns [33, 34]. Faizi et al. [29] for ex-ample reported a relatively low MPL of 2.35 ± 0.39 cm in197 term neonates in Indonesia. Few African studieshave been published. Jarrett et al. [24] in Nigeria re-ported a slightly higher MPL of 3.4 ± 0.48 cm. However,the characteristics of their study population were quitedifferent. The study included preterm, term and postterm babies, whilst only term babies were analyzed inthe current study. Elsewhere in Africa, Kholy et al. [35]also reported a marginally higher MPL of 3.4 ± 0.37 cmin 150 Egyptian neonates. In Caucasians, Schonfeld et al.[14] published a relatively higher MPL in full-term infantof 3.75 ± 0 cm, while Feldman and Smith [3] and Flatauet al. [16] published an MPL of 3.5 ± 0.7 cm and 3.5 ±0.4 cm, respectively.Fewer studies have reported penile width in publishedliterature. This study found an MPW of 1.05 ± 0.1 cm.Semiz et al. [30] reported a comparable MPW of 1.04 ±0.09 while Akin et al. [21] reported a comparativelyhigher MPW of 1.21 ± 0.11 cm. The technique for themeasurement of penile width was not stated in theformer whilst the latter study measured the penile widthin the midshaft using a circular scale with measurementsbeing taken to the nearest even 2 mm. Jarrett et al. [24]reported a relatively higher MPW of 1.2 ± 0.14 cm. Herethe penile width was measured as the transverse diam-eter in the middle of the penile shaft using a ruler. Thiscurrent study measured penile width in its widest diam-eter along the shaft with a caliper which measures to thenearest 0.01 mm. Differences in measurement tech-niques and accuracy of the scales employed could play arole in the variation of published MPW values. Therehave also been reports of a significant association be-tween penile width and other anthropometric parame-ters as well as maternal age [21, 24, 36]. Consequently,differences in the characteristics of the study populationmay contribute to the variability seen in reported valuesof MPW. Elsewhere, Feldman and Smith [3] has re-ported a comparable MPW of 1.1 ± 0.2 cm in the UnitedStates whereas Sutan-Assin et al. [33] reported a rela-tively low MPW of 0.82 ± 0.33 cm in 336 term babies inIndonesia.Genital size did not vary significantly by parentalsocio-economic status, probably as a result of the lack ofassociation between anthropometric parameters and par-ental socio-economic status. The effect of socioeco-nomic status on genital sizes is likely an indirect one,through an effect on newborn anthropometric parame-ters. No study has examined the effect of socio-economic status on genital sizes per say. However, Leeet al. [19] reported a significant increase in SPL in Ko-rean children when they compared normative data ob-tained in the year 2011 to that of 1987. They attributedthis to a comparative increase in anthropometric indiceslike weight and length/height from improved economicconditions. Genital size also did not vary significantlywith maternal use of herbal medicine during pregnancy.This analysis was done to evaluate for possible hormonaleffects of the ingested herbal medicines, since theirconstituents were largely unknown. MPW was higher(1.15 ± 0.77 cm) in babies of mothers from the Ga-Adangbe tribe but their numbers were too small to com-pute for statistical significance. There was no significantdifference between genital measurements done in thefirst 24 h and those done afterwards. Contrarily, in 63Japanese term newborns Matsuo et al. [31] found thatpenile length measured within 12 h after birth differedsignificantly (0.3 cm 95% CI 0.22–0.34) from values ob-tained 1–7 days postnatally by the same examiner. TheyTable 3 Association of genital size with anthropometricparametersBirth Weight (kgs) Length (cm)Coeff (95% CI) P-value Coeff (95% CI) P-valueMPL (mm) 0.87 (−0.1–1.85) 0.08 0.34 (0.16–0.51) <0.001MPW (mm) 0.57 (0.32–0.81) <0.001 0.11 (0.07–0.16) <0.001Significant p-values are in bold faceAsafo-Agyei et al. International Journal of Pediatric Endocrinology  (2017) 2017:2 Page 4 of 7attributed this to the oedematous prepubic skin hinder-ing sufficient stretching of the penis. However, the sam-ple size was probably too small to establish a definitesignificance and p-values were not given.There was a weak inverse relationship between maternalage and MPL (Coefficient −0.062, 95% CI −0.121 to −0.002;p = 0.04), consistent with what was reported by Romano-Riquer et al. [36]. The association between penile size andmaternal age could be related to the finding that olderpregnant women tend to have lower testosterone levels [37,38], and there is a positive correlation between maternaland fetal testosterone levels [39]. Testosterone has a trophiceffect on the phallus, as demonstrated by Mohamed et al.[40] who reported a positive correlation between penilelength and serum testosterone levels in newborns. Anotherpossibility is that placental aromatase activity, whichmetabolizes fetal androgens into estriol, may increase withincreasing maternal age, thereby resulting in lower fetaltestosterone concentrations. Kaijser et al. [41] howeverfound no correlation between maternal age and placentalaromatase.This study found a significant positive correlationbetween MPL and gestational age (p = 0.04). In multi-variate analysis, likely because of the small range of ges-tational ages (only term neonates delivered at 38–42weeks of gestation were included); this correlation wasno longer statistically significant. Other studies have alsoreported a positive correlation between MPL and gesta-tional age [23, 34]. Jarrett et al. [24] found no correlationbetween MPL and gestational age. The reasons for theseinconsistencies in finding associations are most likelymulti-factorial, possibly including differences in studymethodology and ethnicity [17]. Similar to Jarrett et al.[24], this study did not find any correlation betweenMPW and gestational age. In a multiple linear regressionanalysis with post hoc analysis, babies delivered by SVDhad a significantly higher MPL than those delivered byC/S (p = 0.038). We performed this analysis to find outwhether the inclusion of babies delivered by other meansapart from SVD can influence mean genital size. Kutlu[20] in Turkey recruited only babies delivered by SVD,but most other published studies did not state the modeof delivery [17, 21, 22, 24, 30, 32, 42]. The reason forour finding was not clear. More studies need to be doneto clarify this. Our study specifically excluded babieswith breech presentation because of its known associ-ation with hypopituitarism. Debate is ongoing aboutwhether breech presentation is the cause or consequenceof hypopituitarism [43]. Hypopituitarism has also beenassociated with instrumental delivery [5].In this study, MPL was positively correlated with length(p < 0.001) but not with birth weight (p = 0.08) whileMPW was proportionally correlated with both anthropo-metric parameters (p < 0.001 for all). These observationsclosely mirror those of Akin et al. [21]. Likewise, other au-thors have reported a positive correlation between MPLand birth length [20, 23, 30, 34, 44], although majority alsofound a positive correlation with birth weight as well,unlike this study [23, 30, 34, 44]. Jarrett et al. [24] andCheng & Chanoine [17] found no correlation betweenMPL and birth weight or length. Jarrett et al. [24] alsofound a positive correlation between MPW and birthweight and length. In contrast, Cheng and Chanoine [17]found no significant correlation between MPW and birthweight or length.Whether penile length at birth correlates with penilelength in adults is unclear. There is to our knowledge nolongitudinal study on this topic and no studies directlycomparing penile lengths in neonates and adults of di-verse origins. Penile length seems to be relatively similarin both neonates and adults from Nigerian and Cauca-sian descent [14, 24, 45].ConclusionsIn comparing penile size across studies, characteristicsof the study population including gestational age, birthweight and length, mode of delivery and maternal ageshould be taken into consideration. More importantly,over/under-diagnosis of micropenis may occur with itsattendant unnecessary investigations and treatment iflocal normative values for penile size are not established.LimitationsMeasurements were done by two examiners and couldhave introduced an error due to inter-observer variabil-ity. However, an extensive training was done and a sub-set of study subjects was examined by both 2 examinersto evaluate and control for variability, which remainedinsignificant throughout the study.Additional fileAdditional file 1: Penile length Ghana. (TXT 75 kb)AbbreviationsCI: Confidence interval; Coeff: Correlation coefficient; KATH: Komfo AnokyeTeaching Hospital; MPL: Mean penile length; MPW: Mean penile width;SPL: Stretched penile lengthAcknowledgementsSBAA, EA and JPC are members of Global Pediatric Endocrinology andDiabetes (GPED, www.globalpedendo.org), which supported the study. Theauthors will like to acknowledge Prof Margaret Zacharin, the staff of KATHObstetrics and Gynaecology department and the co-ordinators and fellowsof the PETCWA programme.FundingThis research was jointly funded by Global Paediatric Endocrinology andDiabetes and the European Society for Paediatric Endocrinology.Asafo-Agyei et al. International Journal of Pediatric Endocrinology  (2017) 2017:2 Page 5 of 7Availability of data and materialsThe dataset (Penile length Ghana.txt) analysed during the current study hasbeen added as an Additional file 1.Authors’ contributionsSBAA participated in the study design, data collection and entry andmanuscript writing. EA sought for ethical clearance, participated in the studydesign, data collection and entry and supervision and completion of finalmanuscript. JPC participated in the study design, supervision and completionof final manuscript. SBN participated in the study design, statistical analysisand completion of final manuscript. All authors read and approved the finalmanuscript.Competing interestsThe authors declare that they have no competing interests.Consent for publicationNot applicable.Ethics approval and consent to participateEthical approval was obtained from the Committee on Human Research,Publications and Ethics of KATH/Kwame Nkrumah University of Science andTechnology, Kumasi, Ghana. A written informed consent was obtained fromall parent(s) of study subjects.Author details1Department of Child Health, Komfo Anokye Teaching Hospital, Kumasi,Ghana. 2Endocrinology and Diabetes Unit, British Columbia’s Children’sHospital, University of British Columbia, Vancouver, BC, Canada.Received: 5 August 2016 Accepted: 19 January 2017References1. Phillip M, De Boer C, Pilpel D, Karplus M, Sofer S. Clitoral and penile sizes offull term newborns in two different ethnic groups. J Pediatr EndocrinolMetab. 1996;9:175–9.2. Lee P, Mazur T, Danish R, Amrhein J, Blizzard R, Money J, et al. 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Brit J Urol Int. 2015;115:978–86.•  We accept pre-submission inquiries •  Our selector tool helps you to find the most relevant journal•  We provide round the clock customer support •  Convenient online submission•  Thorough peer review•  Inclusion in PubMed and all major indexing services •  Maximum visibility for your researchSubmit your manuscript atwww.biomedcentral.com/submitSubmit your next manuscript to BioMed Central and we will help you at every step:Asafo-Agyei et al. International Journal of Pediatric Endocrinology  (2017) 2017:2 Page 7 of 7

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