In the 1960s and 70s, a Canadian boy raised as a girl was held up as proof that upbringing, not biology, makes us feel male or female.1BBC. The John Money Experiment: A Case of Nature vs. Nurture The boy never accepted the female identity he was given and later lived as a man, so the case ended up arguing the opposite of what was claimed.2PubMed. Sex reassignment at birth. Long-term review and clinical implications It is now remembered as much for how one family was misled and harmed as for what it says about nature and nurture.
What Happened to Bruce Reimer
Bruce Reimer was born in Canada in 1965, one of a pair of boys who were identical twins, meaning they came from a single egg and shared the same genes.3The Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case At about 8 months old, a circumcision meant to ease his difficult urination went wrong and destroyed his penis.4PubMed Central. Paternalism in DSD Management: A Real and Present Threat The damage could not be repaired, so his parents went looking for help and found John Money at Johns Hopkins Hospital.5The Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case
Money advised them that raising Bruce as a girl was in his best interest and recommended surgery.6embryo.asu.edu. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case Doctors said early action gave the best chance of success, and nobody gave the parents a clear picture of how experimental the plan was.
Surgeons removed his testes and damaged penis, built a vulva-like structure, and opened a small hole in his lower abdomen for urination.7The Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case He was renamed Brenda and raised as a girl. Because the testes are the body’s main source of testosterone, Brenda’s body would depend on medical hormones later, and in adolescence he was given estrogen to grow breasts.8The Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case
The twin made the case tempting for Money. Bruce’s brother, Brian, shared the same genes and had grown in the same womb, and Brian was raised as a boy. That gave Money a built-in comparison for testing whether upbringing could set gender.
Money’s Theory That Upbringing Makes Gender
Money argued that gender was shaped by society and could be changed in early childhood.9embryo.asu.edu. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case He held that gender role builds up through life experiences and depends on the sex a child is raised as, not on biology alone.10Max Planck Institute for the History of Science. The John Money Experiment: A Case of Nature vs. Nurture Today experts separate gender identity, a person’s inner sense of being male or female, from gender roles, the behaviors a society expects of men or women.11icliniq.com. How Gender Identity Differs From Gender Role?
That distinction explains where the case went wrong. Money could make Brenda wear dresses, which shaped her role. He could not make her feel female, which is identity. His reports blurred the two and treated outward compliance as success.
Money believed timing was crucial. In his view, a child is flexible about gender early in life, and the window closes at some point in early childhood, so quick action seemed necessary. That is why the plan insisted on reassigning Bruce while he was still a baby, before he had much sense of himself as a boy. The theory also implied that doubt or confusion had to be avoided, which is why Brenda was never told the truth.
Brenda was made to wear dresses and was steered toward dolls and playing with girls.12Simply Psychology. Dr. John Money Gender Experiment Reimer Twins In sessions with Money, the twins said they were made to inspect each other’s genitals and rehearse sexual positions, which Money called healthy sexual play.13The Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case Those sessions are now seen as abuse. The children could not consent, they were kept ignorant of the purpose, and Reimer later described the sessions as traumatic.
Brenda was never told she was born male, and she unknowingly served as Money’s research subject.14The Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case The yearly visits to Money were meant to check that the reassignment was holding and to reinforce it. Because he was both the doctor and the researcher, he had a stake in reporting that the plan was working.
How the Case Was Reported as a Success
From the time Brenda was about five, Money published the case under the name John/Joan.15BBC. The John Money Experiment: A Case of Nature vs. Nurture It became a sensation and appeared widely in textbooks as proof of the power of nurture.16BBC. The John Money Experiment: A Case of Nature vs. Nurture Some feminists saw it as evidence that differences between men and women were social, not biological.17BBC. The John Money Experiment: A Case of Nature vs. Nurture Money’s published accounts said the child was developing as a normal girl.18PubMed. Sex reassignment at birth. Long-term review and clinical implications
The child’s own distress at home never made it into print. A success report on a young child was also too early to prove anything, since a person’s sense of gender can become clearer in adolescence.
The child’s identity was hidden, so outsiders couldn’t follow up, and Money controlled access to the case. The story also fit the scientific and political mood of the time. Doubts were raised, but they lacked new information until the 1990s.
The stakes went beyond one family. Money had reported 45 genetic males raised as females, most because of a very small penis at birth.19PubMed. Ablatio penis: normal male infant sex-reassigned as a girl His approach helped make early surgical reassignment a standard treatment for about four decades.20Cardozo Journal of Law & Gender. David Reimer’s Legacy: Limiting parental discretion Doctors treating babies born with unclear genitals looked to the case as evidence that a baby could be raised as either sex, which gave them confidence to operate. Some doctors doubted the reports even then.21PubMed. Recollections and Reflections on the Reimer Twin Case in Canada: Interview with Dr H. Keith Sigmundson/Tribute and Twin Research Review: Remembering John L. Hopper; Nonhuman Primate Twinning/Human Interest: The Accidental Twins film; Different Looking Identical Twin Newborns
Brenda Becomes David
The signs that the plan was failing began in childhood. He resisted dresses and girls’ toys, and he was teased at school for seeming boyish. None of this appeared in Money’s papers.
In early adolescence Brenda refused more estrogen and stopped seeing Money.22Los Angeles Times. David Reimer, 38; After Botched Surgery, He Was Raised as a Girl in Gender Experiment Then, around age 14 or 15, his father told him the truth about his birth.23Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case Hearing it gave a name to feelings he had carried for years, and he described it as making sense of why he had felt so out of place. He took the name David, after the Biblical David who fought Goliath.24Los Angeles Times. David Reimer, 38; After Botched Surgery, He Was Raised as a Girl in Gender Experiment By 21 he had testosterone, breast removal and surgeries to rebuild a penis.25Embryo Project Encyclopedia. David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case
In 1997 Milton Diamond and Keith Sigmundson found the adult behind John/Joan and compared his records with Money’s claims.26Simply Psychology. Dr. John Money Gender Experiment: Reimer Twins They showed the reassignment had failed and that he had lived as a man for years.27PubMed. Sex reassignment at birth. Long-term review and clinical implications Reimer said he never felt any fit with a female identity.28UBC Press. The Man Who Invented Gender: Engaging the Ideas of John Money
His twin Brian, who had schizophrenia, died of an overdose that was apparently suicide, and David reportedly felt responsible.29the Guardian. Being Brenda David himself died in 2004 at age 38, by suicide.
His death is not simple proof of anything. He faced many stresses: the surgeries, the abuse, his brother’s death, and, reports say, job loss and marriage trouble.
Does the Case Prove Gender Is Biological
One case can’t settle the question, so researchers looked at other boys raised as girls because of birth defects, to see whether most accepted the identity they were raised in or moved away from it. Of 14 such children assigned female at birth, 8 declared themselves male by adolescence or later.30PubMed Central. Discordant Sexual Identity in Some Genetic Males with Cloacal Exstrophy Assigned to Female Sex at Birth All 16 children in the wider group, including those raised as boys, showed interests typical of boys, whatever their upbringing.31PubMed Central. Discordant Sexual Identity in Some Genetic Males with Cloacal Exstrophy Assigned to Female Sex at Birth
These results show a tendency, not a rule. Six of the 14 did not switch. The boyish interests suggest play preferences may be shaped before birth, though that is a pattern in a small group. A larger review found the risk of switching to male was raised but not certain, so hormones before birth don’t fully decide identity.32PubMed. Gender identity outcome in female-raised 46,XY persons with penile agenesis, cloacal exstrophy of the bladder, or penile ablation
Hormones may be part of the explanation. Hormones like testosterone before birth help make brains more typically male.33PubMed. The role of steroid hormones in the sexual differentiation of the human brain Women exposed to high levels of these hormones in the womb have brain structure partway between typical women and men.34PubMed Central. Enduring prenatal androgen effects on the female brain Testosterone is thought to act on the developing brain during a limited period, which would explain lasting effects after birth.
Brain structure and genes add to the picture. One small brain region is larger in men, and it was female-sized in a small group of transgender women.35Sex and the Brain. A sex difference in the human brain and its relation to transsexuality In twins, if one identical twin is transgender, the other is about 21% likely to be too, versus 8% for non-identical twins.36PubMed Central. Using twin data to examine heritable and intrauterine hormonal influences on transgender and gender diverse identities Estimates of genetic influence vary widely, from none to strong.37PubMed Central. Genetic and Environmental Contributions To Gender Diversity: A Systematic Review of the Twin Literature
Reimer’s case shows what it can and can’t. Unlike most children in Money’s reassignments, he was born with typical male anatomy, and he spent his early months as a boy before the change. It shows upbringing failed for him, not that it never matters. Gender roles clearly are still learned. Biology seems to set a strong tendency, and experience shapes how it’s expressed.
How the Case Changed Medicine
After 1997, many doctors began questioning infant sex assignment.38Cardozo Journal of Law & Gender. David Reimer’s Legacy: Limiting parental discretion Surgery on infants done only for appearance came to be widely seen as unjustified.39Cardozo Journal of Law & Gender. David Reimer’s Legacy: Limiting parental discretion Many health bodies now recommend delaying elective procedures until the child can take part in the decision.40AMA Journal of Ethics. A Call to Update Standard of Care for Children With Differences in Sex Development
The shift matters most for children born with atypical sex anatomy, sometimes called intersex or differences in sex development, and for their parents. Before it, surgery was often done early so a child’s body would look typical, with the aim of easing the family’s worries. Now many doctors treat a decision about appearance as something that can wait, and they separate it from procedures needed for the child’s health. That does not mean no surgery is ever done, because some operations protect health and are not only cosmetic.
Parents are encouraged not to feel forced to decide in the first weeks of life. Families are often advised to seek care from teams with several kinds of specialists and to ask about the long-term effects of each choice. They are also asked to consider that a child may grow up to hold a different identity from the one assigned at birth. Doctors now emphasize honesty with families and with the child, and the child’s own voice is treated as central.
The case left ethical lessons too. Keeping a patient’s history secret from them caused harm. Treating a person as a research subject without consent is unacceptable. And published success claims need independent follow-up.
The debate continues. The case remains a reference point in arguments about gender and biology.41UBC Press. The Man Who Invented Gender: Engaging the Ideas of John Money Some scholars argue it is used to dismiss all of Money’s ideas unfairly.42UBC Press. The Man Who Invented Gender: Engaging the Ideas of John Money
Where to Learn More About the Story
John Colapinto’s book As Nature Made Him is widely cited in popular and scholarly writing on the case.43UBC Press. The Man Who Invented Gender: Engaging the Ideas of John Money It follows the family over many years and draws on interviews, so it gives a detailed account of daily life in the experiment. It is written for general readers and is a good starting point if you know the case only from summaries. It tells the story largely from the Reimer family’s side, so it presents a particular view of Money.
Reimer also gave interviews to the media in the early 2000s. Hearing him speak in his own words conveys how he felt in a way a written summary cannot. Documentaries compress years into an hour, so they usually leave out the scientific debate and focus on the personal story.