Boulder, Colorado, where I was born and raised, is sometimes called the fittest city in America. Septuagenarians go skiing before work, high-school delinquents hang out at the climbing gym, and people do not so much hike as trail run. Every year, the town hosts the BOLDERBoulder, one of the largest road races in the country and a sort of festival day in honor of the local god of exercise. I first ran the ten-kilometre course when I was six, not an unusual age of initiation for locals, and discovered that I was a bizarrely good runner. Three years in a row, I finished first out of some four hundred girls my age, and fifth or sixth out of a similar number of boys. At twelve, the last year I raced, I ran what was then the sixth-fastest time ever recorded by a twelve-year-old girl in the race’s three decades of results. My parents were baffled. This was no gene of theirs, surely, but it also didn’t seem to be hard work. I didn’t care about running, and I never trained.
What I did work at, harder than I have worked at anything since, was soccer. Colorado’s Front Range produces many excellent soccer players—all of the United States’ goals in last summer’s Women’s World Cup were scored by players who grew up within an hour’s drive of Boulder—and the great disappointment of my cushy childhood was realizing that I was not to be one of them. I failed, year after year, to make the local club’s first team. I made my high school’s varsity team as a sophomore but didn’t start a game until I was a senior. If you had asked me at fifteen if I would rather be a little better at soccer or one day find true love, I wouldn’t have paused to think. I didn’t dream at night of love but of wide green spaces, well-timed tackles, and chipped shots.
The other dream of my youth, which I did not then see as bearing any relation to athleticism, was to be rid of my acne. From puberty on, it wavered between demoralizing and disfiguring. At the end of college, I finally got on Accutane, which left me with a toxified liver and—for two glorious years—the skin of a baby. Then the acne came back, worse than ever. It looked like I had picked a fight with a wasp’s nest and lost. In the fall of 2022, I moved to Mexico City and saw a dermatologist there. I wanted another round of Accutane, liver be damned. She agreed, all but wincing, that the situation was dire, but insisted that hormonal causes like polycystic ovary syndrome, or P.C.O.S., first be ruled out. This was annoying: the blood tests were expensive, and several American dermatologists had explained to me that hormonal acne fluctuates over the menstrual cycle, whereas mine stayed bad all month long. But I was desperate, and I did as she said.
A week later, the blood tests came back. In a one-room office in downtown Mexico City, a grandmotherly gynecologist who called me “hija” and my breasts “mamas” explained that I had a condition called hyperandrogenism: an excess of the sex hormones associated with men, including testosterone, and very likely the cause of the past decade of acne. My estrogen levels were considerably lower than those of most premenopausal women; they were typical of prepubescent children of either sex. My free-testosterone levels—one of three forms of the hormone—were well above the usual female range. In most women my age, the concentration of androstenedione, a precursor to testosterone, is between thirty and two hundred and eighty-five nanograms per decilitre. Mine was six hundred and twenty. It was all the weirder, the doctor said, because for years I had been on hormonal birth control, which tends to suppress androgen levels.
I received all of this in rapid medical Spanish. There was a processing lag, and then shock and something like fear. I remember nodding a lot, and wanting to cry. But I had never identified as anything other than a girl or a woman, and, after five minutes’ dazed reflection, I saw no reason why a blood test should change that. And what a relief to know that my acne stemmed not from, say, sins committed in a previous life but from something as blameless and adjustable as hormones. The kindly doctor suggested three medicines: a dietary supplement, a new birth control containing drospirenone, and a pill called spironolactone. This last, I happened to know, is prescribed to trans women in the U.S. as a component of hormone-replacement therapy. I would learn that it can also be used alongside birth control by intersex women who must lower their total testosterone levels in order to compete in certain élite sports.
Like many other longtime followers of women’s sports, I had in the past few years watched the debate over the sex line grow—surreally—from a debate among fans of women’s track to a national wedge issue. “If you take out a loan, you pay it back,” Tim Scott said this year during the first Republican primary debate. “If you commit a violent crime, you go to jail. And, if God made you a man, you play sports against men.” This summer, Nikki Haley called “biological boys playing in girls’ sports” the “women’s issue of our time.”
Before my blood tests, on the rare occasions when I considered my stance on the issue, I had viewed myself as a member of the putative victim group—sports-playing cis women who really like to win—even as I was not particularly afraid that increased gender diversity would destroy women’s sports as we know them. (Anyone who thinks that legions of men will declare themselves women only to compete in an easier division is, I think, missing something crucial about the nature of masculine pride.) After the blood tests, I was still sports-playing, still cisgender, and still tediously competitive. But now, in a sporting world that increasingly divided the sexes based on hormone levels, I was less sure about who was the threatened and who was the threat.
The rationale for separating men and women in élite sports is well established. Across many sports with quantitatively measurable results, the best men perform between nine and twelve per cent better than the best women. In sports that rely on explosive strength, the sex gap is even bigger: a fifteen-year-old boy has jumped farther than any woman on record. Male athletic superiority is not absolute—women are better at very long-distance swimming, for example, and a Brazilian woman named Maya Gabeira surfed a bigger wave than anyone else in the 2019-20 season. Nor does it hold true across time: improvements in nutrition, equipment, recruitment, and training have led the best women today to run as fast as the best men did a hundred years ago. But, among contemporaneous athletes, the pattern of dominance is uncontroversial. The United States Women’s National Soccer Team, to my abiding shame, once lost, 2–5, in a scrimmage against teen-age boys on an F.C. Dallas developmental team.
The hard question for sports administrators, then, is not whether to have a sex line in élite sports but how, exactly, to distinguish between brawny but nevertheless “legitimate” women and dishonest male infiltrators. This proved, as early as the nineteen-thirties, to be difficult. Joanna Harper recounts in “Sporting Gender,” a lively history of intersex and trans athletes, that the best runners in the women’s division at the time tended to be bulky and sharp-jawed; they had gravelly voices and, as an added strike, often were not married. Helen Stephens, Stella Walsh, and Käthe Krauss, respectively the gold, silver, and bronze medallists in the hundred-metre sprint at the 1936 Berlin Olympics, all faced suspicion around their sex. The fourth-place finisher, a German teammate of Krauss’s, complained that she was “the only woman in the race.”
At the time, it was not unheard of for a top American athlete to allay suspicions about her sex by adopting more feminine dress or entering into a marriage of convenience. (Sex and sexuality were often conflated.) Stephens, who would later have a forty-year partnership with a woman, defended herself by suggesting that she was attractive to men: she liked to tell a story about the Olympic host, Adolf Hitler, grabbing her ass. “Helen is absolutely a girl,” Stephens’s mother told reporters, adding that she “attends dances regularly at college.” On the other hand, Walsh, who was also a lesbian, did not keep up with such feminine niceties as shaving her legs. “I am not beset by the temperamental tempests which women are supposed to have,” she reportedly said.
Decades later, Walsh, who spent the rest of her career coaching kids in Cleveland, would be killed in a parking-lot robbery. The autopsy results, which were leaked, revealed that she had atypical genitalia: a hole in the perineum for urination, but also small testes. Further testing showed that she had what is called a mosaicism of chromosomes: in her case, some cells with a single X chromosome and others with XY. Walsh’s ex-husband, whom she had married in order to switch her running eligibility from Poland to the United States—they divorced after three months—later told journalists that they’d had sex infrequently, and only with the lights off. A close friend described Walsh as “a self-conscious woman” who “lived a tragic life.”