Anogenital distance and umbilical cord testosterone level in newborns in Zaria, Northern Nigeria

Abstract

The anogenital distance (AGD) is the distance between the anus and the base of the penis in males and anus to fourchette (AF) distance in females and is a sexually dimorphic index that, on average, is twice as great in males as in females, so it is used as an indicator of appropiate masculine development. In this study, the anogenital distance (AGD) and anthropometric measurements such as birth weight, birth length, head circumference and placenta weight of 200 newborns (100 male, 100 female) were taken and umbilical cord serum was assayed for testosterone concentration using Radioimmunoassay (Microwell). Data obtained were analysed using Student t-test and Pearson’s Correlation Analysis as applicable. Results revealed that mean total anogenital distance was 22.53±0.70mm, and it was significantly higher in males: 31.11±0.64mm than in females: 13.89±0.26mm and we observed that there was positive correlation between birth weight and AGD in females. In males head circumference correlated positively with AGD. The mean cord testosterone concentration was 2.78±0.30ng/ml in males and 2.09±0.22ng/ml in females and did not have any significant correlation with anogenital distance. It was concluded that AGD of the population studied, though high was not significantly higher than AGD in other parts of the world and umbilical cord testosterone level did not have any significant effect on AGD.

Keywords: Anogenital distance, Ethnicity, Umbilical cord testosterone, Anthropometry

Nig. J. Physiol. Sci 26(June 2011) 023 – 028