True Hermaphroditism with XX/XY Mosaicism, Probably Due to Double Fertilization of the Ovum1

A 20-yr-old chromatin-positive true hermaphrodite, raised as a boy, presenting with breast development and menstruation, is described, who had a left ovary and a right ovotestis. Ovarian tissue appeared histologically normal, with complete maturation of graafian follicles and corpus luteum formation. In the testicular part of the ovotestis, spermatogenesis was incomplete; Leydig cells appeared normal. XX/XY mosaicism was found. Gonadal stimulation by chorionic gonadotropin, under adrenal suppression, showed normal function of the left ovary, considering that the test was performed during the hypothermic phase of the cycle. In contrast, the Leydig tissue of the ovotestis was hormonally inactive, and ovarian secretion was notably insufficient. This is perhaps due to prolonged treatment by testosterone. Serologic studies showed a double haptoglobin phenotype, suggesting that the XX/XY mosaicism was due to double fertilization of the ovum.