Clitoral sizes and anogenital distances in term newborns in Nigeria

Estimation of Reference Values for External Genitalia Parameters in North Indian Preterm and Term Female Newborns

OBJECTIVES

To establish gestation-wise normative data of external genitalia measurements in North Indian term and preterm female newborns.

METHODS

In this cross-sectional descriptive study, institutionally-born female neonates between 28-42 wk gestation were consecutively enrolled between 24-72 h of life. Newborns with major congenital malformations, chromosomal anomalies, multifetal gestation and birth injuries were excluded. Data on various genital measurements were collected [Clitoral length (CL), clitoral width (CW), ano-clitoral distance (AGDAC), ano-fourchette distance (AGDAF) and anogenital ratio (AGR)].

RESULTS

One hundred ninety-eight of 508 neonates (39%) were preterm and 310 (61%) were term. Mean (± SD) CL and CW were 4.6 ± 1.8 mm and 3.9 ± 1.6 mm, respectively. Mean (± SD) values for AGDAF, AGDAC and AGR were 9.3 ± 1.8 mm, 30.2 ± 3.9 mm, and 0.31 ± 0.05, respectively. According to these results, term female newborns with CL more than 7 mm and/or CW more than 6 mm (95th centile) warrant evaluation for clitoromegaly. An anogenital ratio greater than 0.45 should be considered as a sign of virilization in a female neonate. Gestation-wise percentile charts for CL, CW, AGDAF, AGDAC and AGR were generated.

CONCLUSIONS

The percentile values defined in the study can serve as local normative data for accurate interpretation of genital measurements in North Indian female newborns and enable health care professionals for early identification of genital virilization.

Generation of South Indian Data for Normal Clitoral Dimensions and Anogenital Ratio in Term Neonates

Introduction

Assessment of genitalia is an important part of the neonatal examination. Regional, racial, and ethnic variations in phallic length have been documented. Clitoral dimensions may also show similar variations. Normal values for neonatal clitoral measurements may help the pediatrician/neonatologist to accurately diagnose clitoromegaly and underlying etiology to guide appropriate investigations. Data on clitoral measurements is limited with only one study from India (Kolkata). Hence we aimed in this study to generate south Indian data on neonatal clitoral dimensions, anogenital distance, and anogenital ratio. Two hundred and fifty two hemodynamically stable term female neonates without ambiguous genitalia/vulval masses born in a community hospital. Hospital-based cross-sectional study. 1. To measure clitoral dimensions, anogenital distance, and anogenital ratio in female neonates. 2. To correlate clitoral dimensions, anogenital distance, and ratio with anthropometric measurements, gestational age, and maternal comorbidities.

Methods

Measurements were recorded using a digital vernier caliper, under strict aseptic precautions with labia majora gently separated and the baby held in a frog-leg position. Clitoral length, width, and anogenital distance were measured and anogenital ratio and clitoral index were calculated.

Results

In term neonates, the mean ± SD of clitoral length (CL), clitoral width (CW), anogenital ratio (AGR) were 6.34 ± 1.75 mm, 6.39 ± 1.27 mm and 0.39 ± 0.05, respectively. The 3rd and 97th centiles for mean clitoral length were 3.55 and 9.93 mm, for mean clitoral width were 3.37 and 8.35 mm, and for AGR were 0.28 and 0.48, respectively. These clitoral dimensions in south Indian neonates were higher than those from East India (Kolkata), lower than Nigerian babies, and similar to Israeli neonates. Mean CL and CW had no statistical correlation with birth weight, gestational age, head circumference, or length in term neonates. A significant correlation was noted between pregnancy-induced hypertension and mean clitoral width, and between gestational diabetes and AGR.

Conclusion

Normative values for clitoral dimensions (length and width) and AGR for south Indian term female neonates have been established. 97th centiles of 9.93 mm (CL) and 8.35 mm (CW) and 0.48 mm (AGR) may be used as practical cut-offs to diagnose clitoromegaly and virilization. Clitoral measurements had no statistical correlation with birth weight, gestational age, or anthropometry. Clitoral measurements exhibit ethnic and racial differences, thus emphasizing the importance of regional cut-offs and need for more studies from different parts of India on CL.

Nonvirilized Genitalia in 3 Female Newborns With the Salt-Wasting Congenital Adrenal Hyperplasia Phenotype

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, a form of primary adrenal insufficiency characterized by impaired cortisol secretion and elevated androgen production, is the leading cause of atypical genitalia in the female newborn. Females with classic CAH, either salt-wasting or simple-virilizing form, usually present at birth with atypical genitalia ranging from clitoromegaly to male-appearing genitalia, due to in utero to elevated androgens (androstenedione and testosterone). Females with mild nonclassic CAH usually present with typical genitalia. Proving the importance of always keeping an open mind for exceptions to the rule, we report on 3 female newborns who presented with the nonvirilized genitalia, salt-wasting CAH phenotype and genotype most consistent with simple-virilizing CAH. It is only through a positive newborn screen identifying the females with CAH that they were diagnosed before developing adrenal and/or salt-wasting crisis.

Anogenital Distance in Healthy Infants: Method-, Age- and Sex-related Reference Ranges

CONTEXT

The use of anogenital distance (AGD) in clinical and epidemiological settings is increasing; however, sex-specific reference data on AGD and data on longitudinal changes in AGD in children is scarce.

OBJECTIVE

To create age-, sex-, and method-related reference ranges of AGD in healthy boys and girls aged 0-24 months, to assess the age-related changes in AGD and to evaluate the 2 predominantly used methods of AGD measurement.

DESIGN

The International AGD consortium comprising 4 centers compiled data from 1 cross-sectional and 3 longitudinal cohort studies (clinicaltrials.gov [NCT02497209]).

SETTING

All data were collected from population-based studies, recruiting from 4 maternity or obstetric centers (United States, Cambridge [United Kingdom], Odense, and Copenhagen [Denmark]).

SUBJECTS

This study included a total of 3705 healthy, mainly Caucasian children aged 0-24 months on whom 7295 measurements were recorded.

MAIN OUTCOME MEASURES

AGDAS (ano-scrotal), AGDAF (ano-fourchette), AGDAP (ano-penile), AGDAC (ano-clitoral), AGD body size indices (weight, body mass index [BMI], body surface area, and length), and intra- and interobserver biases.

RESULTS

We created age-specific reference ranges by centers. We found that AGD increased from birth to 6 months of age and thereafter reached a plateau. Changes in AGD/BMI during the first year of life were minor (0-6% and 0-11% in boys and girls, respectively).

CONCLUSIONS

Reference ranges for AGD can be used in future epidemiological research and may be utilized clinically to evaluate prenatal androgen action in differences-in-sex-development patients. The increase in AGD during the first year of life was age-related, while AGD/BMI was fairly stable. The TIDES and Cambridge methods were equally reproducible.