Early gender assignment in true hermaphroditism

True hermaphroditism is a rare form of intersex anomaly where both male and female gonads are present. True hermaphrodites diagnosed in the past have been preferentially reared as males. However, based on the appearance of their external genitalia and the ability to reconstruct a functional genitourinary system, most of these children should be raised as girls. Between 1968 and 1987, we managed eight children with true hermaphroditism. The karyotypes were as follows: five 46XX, one 46XY, one 47XXY, and one 46XX/mosaic. Gonadal distribution was bilateral (two ovotestes) in two, lateral (testis and ovary) in two, and unilateral (ovotestis and ovary) in four. Seven patients were diagnosed shortly after birth. Six were raised as girls, two as boys. Based on a review of the relationship of external-internal genitalia, gonads, and karyotype of our own patients and those published by others, we believe that the appearance of the external genitalia alone allows a prompt and definitive gender assignment in infancy. This led us to develop a classification of external genitalia based on the following characteristics. Class I represents normal female genitalia, class II an enlarged clitoris, class III partially fused labioscrotal folds, class IV fused labioscrotal folds, class V a hypoplastic scrotum and penoscrotal hypospadias, and class VI represents normal male genitalia. We had two patients that were class II, two class III, three that were class IV, and one to IV should be raised as females; in class V, male gender assignment is preferable. This classification, based on the appearance of the external genitalia, allows a simple screening and prompt gender assignment in infants identified as true hermaphrodites.