Matched pair of siblings concordant for 46,XY hermaphroditism with female sex assignment, and discordant for erotosexual outcome.

The two siblings in this comparison constitute a matched pair on the basis of concordance not only for prenatal history and diagnosis but also for assigned sex as girls, and for spontaneous hormonal puberty that was not feminizing, but masculinizing. They were further concordant in being surgically and hormonally feminized, with their own informed consent, early in adolescence. Subsequently, they became discordant, for the younger one has lived continuously as a woman, with a feminine gender-identity/role (G-I/R) socially and erotosexually, whereas the older one became self-reassigned to live as a man with a masculine G-I/R socially and erotosexually, hormonally supported on testosterone replacement therapy. Flattening of the chest was readily accomplished by plastic surgery, but phalloplasty was not attempted, primarily because of the technical obstacles and, to a lesser extent, the cost.