How the Olympic Ban on Transgender Women Could Affect All Women Athletes

For years, Kate competed without questioning whether she belonged. Running track gave her close friends, a sense of community, and the satisfaction of getting stronger and faster with each race. Now, her place in the sport feels less secure.

Kate is an intersex woman—intersex being a term used for people born with variations in sex characteristics that fall outside of traditional definitions of male or female bodies. She has Complete Androgen Insensitivity Syndrome, or CAIS, a rare genetic condition in which individuals with XY chromosomes are resistant to androgens, resulting in a typically female external appearance.

The new International Olympic Committee policy requiring genetic testing for women—aimed at ensuring participation is “limited to biological females”—has left the 21-year-old unsure how the rules would apply to athletes like her. 

The move marks a reversal of the IOC’s 2015 decision, which went into effect in 2016, to allow transgender athletes to compete without undergoing gender-affirming surgery. And the decision is also a departure from the IOC’s longstanding policy against such gender tests in part because of their inaccuracies among athletes with differences in sex development, such as CAIS. 

Despite the political attention, very few transgender women have competed at the elite level. Laurel Hubbard, a weightlifter from New Zealand, became the first openly transgender woman to compete in the Olympics at the Tokyo Games in 2021—the only such athlete to do so to date—and did not win a medal.

Under the IOC’s new rules, athletes with CAIS would be exempt from the ban on some intersex women. But Kate says it remains unclear how that exemption would be interpreted or enforced in practice.

“​​The evidence they're citing is about comparing typical men and typical women,” says Kate, a track and field athlete competing at the collegiate level, who asked to use a pseudonym due to fears of harassment. “They're trying to generalize that to these other populations without actually studying intersex women, or women with variations in sex characteristics, or trans women.”

Androgen insensitivity conditions are often described as existing along a spectrum. Critics of the new policy argue that drawing a line between who qualifies and who does not would require clinical judgment—yet where that line would be drawn remains unclear.

What is the new testing for Olympic athletes?  

Under the new policy, female athletes would be required to undergo genetic testing, including screening for the SRY gene. The SRY gene, typically found on the Y chromosome, plays a role in initiating male sex development during early embryonic stages. But scientists say it is only one part of a far more complex process.

“Biological sex in humans is determined by a complex interplay of chromosomal, gonadal, hormonal, and phenotypic (physical) factors,” said Andrew Sinclair, a geneticist who helped discover the SRY gene in 1990. “The presence of the SRY gene alone does not define biological sex.”

Under the policy, athletes who test negative for the SRY gene are eligible to compete in the female category. Those who test positive are generally excluded, with a “rare exception” for some athletes with conditions such as Complete Androgen Insensitivity Syndrome, who are not considered to benefit from testosterone-linked performance effects.

By focusing on the presence of the SRY gene, the policy could exclude some athletes with differences in sex development, including intersex women who have XY chromosomes but were assigned female at birth and have developed as female. An estimated 2% of the population has variations in sex traits, though the true number may be higher, as many people only discover these differences through genetic testing.

The policy applies to IOC events, including the Olympic Games and other competitions such as the Youth Olympic Games, which involve teenage athletes. The IOC says the changes are necessary to ensure “fairness, safety and integrity in elite competition,” citing what it describes as a performance advantage associated with male sex.

For transgender athletes, the reversal from earlier Olympic policy marks a devastating blow.

Chloe Anderson, then a volleyball player at the University of California, Santa Cruz, was featured in a documentary film commissioned by the International Olympic Committee following their 2015 landmark decision. Anderson, the only transgender woman featured, was one of the first trans athletes in a California college or university. The series described her “inspiring journey” to finding herself through sport.

Read more: Letting Transgender Kids Play Sports Can Benefit All Kids

“Volleyball was a safe place for me to be a part of a women's space where my team was all very supportive,” Anderson tells TIME.  “It was the first time in my life that I had done well in school, because I was motivated to play volleyball.” 

After the ruling, Anderson said she was “disappointed,” but not surprised. “I was really hoping they were better than that. I think it's gonna hurt a lot more people than it’s going to help.”

Alun Williams, a professor of sport and exercise genomics at Manchester Metropolitan University, argues that while there is “some understandable concern about their eligibility in women's sport,” sex testing is not an accurate or appropriate response.  

When it comes to intersex women, Williams argues the evidence is “so thin” that there are physical advantages in the sport, and that the research cited by the IOC to justify its policy is “such poor quality, it is laughable.”

“The real gray area is, are people benefiting from that small sort of sensitivity to testosterone in terms of small performance or not?” he continues. “The IOC regulations are now based on the assumption that they are. But there is almost no direct evidence of that.”

How the policy could also affect cisgender women 

While the policy primarily targets transgender women and some intersex women, critics say its effects could extend across the entire women’s field. 

“While this decision will limit or impact very few transgender women, it will impact every intersex woman and every cisgender woman who participates because of genetic testing,” Chris Mosier, an eight-time Team USA triathlete and the first known transgender athlete to represent the United States in international competition, tells TIME. 

Two-time Olympic champion runner Caster Semenya identifies as a cisgender woman, but has faced questions about her sex for nearly two decades. In an opinion piece published with TIME, she called the ruling a “disgrace” and warned that it could “disproportionately impact women from the global South.” 

“Genetic screening is not, and never has been, a way to protect girls and women in sports,” Semenya wrote. “To call it that is to mask a monster. Let’s call this what it is: exclusion, just with a different name.”

The danger of revealing private medical information 

Erika Lorshbough, a lawyer and executive director of the advocacy group interACT who is intersex themselves, explained that many athletes undergoing genetic testing may only learn they have intersex variations during the genetic testing process.

“They will be finding out this life-changing medical information at the same time that they are banned from their sport and publicly outed about it,” they tell TIME. “There are places around the world where this kind of outing is incredibly dangerous. I would like to think the U.S. is not one of those places. But right now it doesn't feel like that to a lot of people.”

Lorshbough and interACT work with intersex youth, and says that even before the new IOC ruling, their team had recorded an increase in harassment of young intersex athletes.

“These girls that we work with who have been willing to step up and share their stories publicly are getting doxxed,” they say. “I've seen people walk right up to them and shout in their face that they are a man.”

Stigma was part of the reason why IOC stopped performing the genetic tests prior to the 2000 Olympics in Sydney. The tests were prone to producing false positives, which were deemed “highly discriminatory,” and found to be full of “functional and ethical inconsistencies,” according to one study published at the time.

“It was stopped because there were so many reports of athletes being told information that they didn't know, the distress that it caused to them and their families,” Williams says. “The stigma that was then applied to them as individuals, either broadly, if they were known about in the media or just within their own circles and so on.” 

Politics over policy?

The policy has also drawn political attention. After the decision was announced on March 26, White House Press Secretary  Karoline Leavitt posted on X that “President Trump's Executive Order protecting women's sports made this happen!”

In February 2025, U.S. President Donald Trump signed an executive order aimed at barring trans women from competing on women’s sports teams in federally funded education programs, and directing agencies to withhold funding from institutions that do not comply.

IOC President Kirsty Coventry has denied the decision is political, saying during an online press conference, “this was a priority for me way before President Trump came into his second term.”

“At the Olympic Games, even the smallest margins can be the difference between victory and defeat,” said Coventry, herself a two-time Olympic gold medalist in swimming. “So, it is absolutely clear that it would not be fair for biological males to compete in the female category.”

Coventry’s comments have done little to assuage transgender athletes like Mosier, however.

“It is clearly related to political pressure, and I believe it’s related to trying to get on this Administration's good side in advance of LA 2028,” he says, in reference to the 2028 Summer Olympics set to be held in Los Angeles. 

“It seems very, very apparent that there wasn’t a new science that would have swayed this decision, and the appropriate experts and participants in this conversation weren’t brought to the table to make it really a robust process.”

For Kate, one of the most difficult aspects of the policy is what it could mean for the next generation. “It made me really sad for all the intersex kids who are dreaming of the Olympics,” she says, explaining that she once thought competing at that level would be “the coolest thing.”

“For that message to be that they're not welcome, or that it's just not an option, made me really sad.”