Mar. 26, 2026, 4:35 PM EDT

Transgender women will be barred from participating in women’s events at the next Olympics, according to a policy the International Olympic Committee announced Thursday.

The decision follows a demand for such a rule from U.S. President Donald Trump, and comes despite objections from researchers and advocates for trans athletes.

The policy change, announced ahead of the 2028 Los Angeles Olympics, aligns with an executive order Trump issued last year directing Secretary of State Marco Rubio to “use all appropriate and available measures” to ensure the IOC “amends the standards governing Olympic sporting events to promote fairness, safety, and the best interests of female athletes by ensuring that eligibility for participation in women’s sporting events is determined according to sex and not gender identity or testosterone reduction.”

The policy will apply to the 2028 Games and all others going forward and is not retroactive, the IOC said. In a video statement announcing the news, IOC President Kirsty Coventry cast the decision as a matter of fairness.

“At the Olympic Games, even the smallest margins can be the difference between victory and defeat,” she said. “So, it is absolutely clear that it would not be fair for biological males to compete in the female category. In addition, in some sports it would simply not be safe.”

As a result of the new IOC policy, eligibility for participation in the female category will be determined by a one-time gene test — the same one World Athletics, the international governing body for track and field, introduced last year. The IOC says the test is highly accurate and nonintrusive, requiring only a cheek swab or blood test.

The policy says athletes who are deemed ineligible to complete in the female category can compete in either the male category or in sports that do not classify athletes by sex, such as equestrian.

But who the policy will actually affect, and how, remains to be seen. There have been few openly trans athletes at the Olympics, Michael Waters, author of “The Other Olympians: Fascism, Queerness, and the Making of Modern Sports,” told MS NOW.

Only one openly transgender woman, Laurel Hubbard, a weightlifter from New Zealand, has ever competed at the Summer Games.

Waters said he sees the IOC’s decision as “a culmination of a broader cultural and political backlash that’s been brewing” regarding the participation of trans people in sports. The U.S. Olympic and Paralympic Committee also banned trans athletes from competing in the women’s category last summer, he noted, and the international skiing and boxing federations have also implemented mandatory gene testing for the same purpose.

That test has also been a source of controversy.

The test is meant to determine the presence or absence of the SRY gene, found on the Y chromosome, which triggers male reproductive development. But cisgender women and intersex people can also have the gene. At the 1996 Olympics in Atlanta, Waters pointed out, eight women failed the SRY gene test before later being reinstated.

“That was one of many reasons why these tests were banned in the first place,” he said. “They were quite inaccurate, in addition to being discriminatory.”

Andrew Sinclair, the Australian researcher who discovered the SRY gene in 1990said last year that he disagreed with World Athletics’ decision to use the test to determine biological sex, calling it an “overly simplistic assertion.”

“Using SRY to establish biological sex is wrong because all it tells you is whether or not the gene is present,” wrote Sinclair, a professor at the University of Melbourne. “It does not tell you how SRY is functioning, whether a testis has formed, whether testosterone is produced and, if so, whether it can be used by the body.”

Sinclair also wrote that a male lab technician could inadvertently contaminate a test, producing a false positive.

The IOC previously mandated “gender verification” for female athletes from 1968 to 1998, but removed the requirement ahead of the 2000 Olympics in Sydney on a “trial basis.” Sinclair wrote that decision came after he and other experts persuaded the IOC to drop it.

Prior to the most recent change, IOC guidelines released in 2021 said there should not be a “presumption of advantage due to biological sex,” leaving eligibility decisions to each sport’s international governing body.

The announcement of the new policy followed an IOC review of the issue beginning in September 2024, which the body says included consultations with a range of experts and an online survey of 1,100 athletes. It marks the highest-profile decision by Coventry, a former Olympic swimmer from Zimbabwe who was elected president of the IOC last March.

It also comes as the Trump administration and its Republican allies have made a pet issue of excluding trans people — and trans women specifically — from public life, women’s sports and American history.

Trump and congressional Republicans are currently aiming to exclude trans women from the forthcoming Smithsonian American Women’s History Museum, as MS NOW recently reported. The president has also signed executive orders stating the government would only recognize biological sex rather than gender identity, that transgender troops could not serve in the military and that minors should not receive gender-affirming care. (Those orders are all the subject of ongoing litigation.)

Trump allies celebrated the IOC decision.

“President Trump’s Executive Order protecting women’s sports made this happen!” White House press secretary Karoline Leavitt wrote on X.

Advocates for LGBTQ athletes predicted the decision would lead to discrimination.

A group that represents intersex youth, interACT, said the decision could harm intersex women athletes, despite the IOC’s assurances that it will not.

“Sex testing invades all women’s privacy, forcing them to give up their personal medical and genetic information for the IOC to determine if they are ‘woman enough’ to compete,” the group’s executive director, Erika Lorshbough, said in a statement. “Any policy that intends to discriminate against transgender athletes also harms intersex women, especially those with chromosomal and hormonal variations. All women deserve the chance to pursue their Olympic dreams.”

The new policy “invites confusion, stigma and invasive scrutiny rather than clarity or safety,” said Brian Dittmeier, director of LGBTQI equality at the National Women’s Law Center.

“At a moment when women athletes continue to face real and persistent inequities — including unequal funding, fewer opportunities and pervasive harassment and abuse — it is deeply harmful to prioritize exclusion over meaningful progress,” Dittmeier added.

Julianne McShane is a breaking news reporter for MS NOW who also covers the politics of abortion and reproductive rights. You can send her tips from a non-work device on Signal at jmcshane.19 or follow her on X or Bluesky.