Country-based reference values and international comparisons of clitoral size in healthy Nigerian newborn infants.
Clitoral size references are useful for diagnosing genital abnormalities. Despite the fact that examining the genitalia is an important aspect of newborn evaluation, few studies have been carried out to determine normal clitoral size in newborn infants. The aim of this study was to establish reference values for clitoral size in Nigerian newborn girls and to compare them with references from other ethnic populations. A total of 244 healthy newborn girls delivered at 28-43 weeks gestation were enrolled in the study, and clitoral lengths and widths were measured at <72 hours. The mean clitoral length was 7.7 mm with a standard deviation of ±1.37 mm, while the mean clitoral width was 4.40 ± 0.89 mm. The clitoral length was significantly longer than those reported for Caucasian (4.00 ± 1.24 mm), Korean (3.82 ± 1.47), Turkish (4.93 ± 1.61) and Japanese (4.30 ± 1.10) babies. The present results make it possible to evaluate clitoral size in Nigerian newborn baby girls in an objective way, to identify genital abnormalities and endocrine disorders. Based on this study, a clitoral length of more than 10 mm would be considered clitoromegaly in a newborn girl in Nigeria.