“Natural Experiments” and Sex Reassignments
The Case for Nature
A small number of newborns suffer from a profound congenital disorder called cloacal exstrophy, which leads to gross abnormalities of the abdominal organs and, in boys, a missing or terribly deformed penis. In the past, doctors often recommended that these genetic boys be reared as girls and undergo surgical sex reassignment to female. The assumption was that a boy born without a penis could not live a normal life as a boy and would be better off reared as a girl. The sex reassignment entailed castration, for boys with cloacal exstrophy are born with testicles even though they have no penises. Thus these XY boys were exposed to normal male amounts of testosterone prenatally, but then they were castrated soon after birth and reared as females. What won out in this case—nature or nurture?
Johns Hopkins University researchers William Reiner and John Gearhart (2004) studied a group of 16 XY children with cloaca! exstrophy. They found that despite surgical reassignment and conscientious attempts by parents to rear most of them as girls, eight of these children rejected their reassigned sex and insisted they were in fact boys (two were reared as boys from the beginning because their parents refused to go along with doctors' recommendations for a sex reassignment). Three children had unclear or undeclared gender identities, and five expressed satisfaction with their assigned female identity. Regardless of their gender identity, however, virtually all of these children expressed markedly masculine interests (e.g., in wrestling, baseball, football, soccer, hunting, and so on). Thus, this natural experiment provides compelling evidence that normal male prenatal exposure to androgens often leads to male-typical behaviors and a male gender identity, even in castrated boys reared as girls. It is important to note that at the time of their last assessments by Reiner and Gearhart, the participants in this study ranged in age from 8 to 20 years (six children were 12 or under), and thus the ultimate gender identities of some of these individuals was not yet known to the researchers.
In the equally fascinating "John/Joan" case, one of two identical twin boys lost his penis due to a botched circumcision procedure. On the advice of doctors, the parents of the twin who lost his penis decided to surgically reassign him to be a girl and rear him as a girl. "Bruce" (the real name of the boy who lost his penis) became "Brenda." Thus one of two identical XY twins was reared as a boy and the other as a girl. Although early reports suggested that the sex reassignment had been successful (Money, 1975), later evidence revealed that Brenda was never really comfortable as a girl. Her masculine demeanor was clear to others; for example, she was taunted by classmates with epithets like "cave woman" (Diamond & Sigmundson, 1997). In adolescence, after learning the truth about her chromosomal sex, early surgery, and sex reassignment, a much-relieved Brenda assumed a male identity and became "David." As an adult, David lived as a man with a wife and adopted children (for a gripping personal account, see Colapinto, 2000). David Reimer's tumultuous life ended tragically in May 2004, when he committed suicide at the age of 38.
Several other cases have been reported of boys who lost their penises early in life and then were reared—with varying degrees of success—as girls. All these individuals were genetic XY males who had had prenatal exposure to typical male levels of testosterone but then were surgically castrated and reared as girls. Many but not all of these XY children later chose to live as males, again suggesting that prenatal exposure to testosterone plays a powerful role in determining later male gender identity and masculine behaviors. Even when such an individual adopts the identity of a female, she may still be sexually attracted to women and show masculine interests (Bradley, Oliver, Chernick, & Zucker, 1998).