The Women’s Tennis Association (WTA) has taken a step beyond most other women’s sports leagues by requiring genetic sex testing for female athletes.

Despite being targeted at transgender women, this policy has the greatest potential to impact intersex cisgender women — especially because many of them don’t know they are intersex. There are no known trans women playing on the WTA Tour. But there are plenty of cis women who will now have to go through medical tests to prove their eligibility. 

Starting this year, women seeking to compete in WTA tournaments must be screened for the SRY gene, which is normally found on the Y chromosome. The result is meant to determine if someone is a “biological male,” but it doesn’t show the full picture.

For example, women with Swyer syndrome or Complete Androgen Insensitivity syndrome would fail the SRY gene test because they have XY chromosomes, despite being born with a vagina and living their entire life as a woman. These are only two out of many known intersex variations.

There are exceptions in the tennis league’s new policy for intersex people. But those exceptions require further tests. They would still have to submit to more testing, provide medical records or possibly involve their physician — all in order to prove their identity. 

When prominent women athletes fail these kinds of tests, or are even suspected of failing them, their identities are routinely publicized and scrutinized on a massive scale. It happened with Caster Semenya, the South African middle-distance runner and two-time Olympic champion, and Imane Khelif, who won Olympic gold in women’s boxing in 2024. Some of the most powerful people in the world hurled anti-trans rhetoric at Khelif, despite the fact that she is not transgender. 

Barbra Banda, an accomplished striker for the Orlando Pride, Florida’s team in the National Women’s Soccer League, has also experienced this kind of harassment — based not on any sex tests, but on how she looks. The soccer league has issued multiple statements supporting her. 

The tennis league’s new policy follows shifting stances from the International Olympic Committee (IOC) and World Athletics, the international governing body for track and field. Both organizations now require genetic sex testing for women athletes in the form of an SRY gene screening. 

Andrew Sinclair, the scientist who discovered the SRY gene, wishes they wouldn’t. 

“Using SRY to establish biological sex is wrong because all it tells you is whether or not the gene is present. 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,” he wrote in a 2025 article for the Murdoch Children’s Research Institute, where he works. 

Regardless, to compete in the 2028 Los Angeles Olympics, all women athletes will be required to pass a SRY gene screening. This impacts sport governing bodies like USA Swimming and USA Track & Field — and all  the other sports governing bodies that are beholden to IOC rules. 

Pressure from the White House is another factor. President Donald Trump signed an executive order last year to keep trans women out of women’s sports, including at the Olympics. Specifically, the State Department was ordered to use all means possible to get the IOC to amend its standards for women athletes.

But leagues like the Women’s Tennis Association are not governed by the IOC or World Athletics. They are privately owned and operated. And at this point, most of them do not have any genetic sex testing requirements.

The 19th reached out to nine women’s leagues for more information. None except for the WTA responded. Based on publicly available information, none of these leagues — except for the WTA — require gene screening for women athletes. 

Most leagues also do not have any public gender eligibility criteria. Although the National Women’s Soccer League (NWSL) adopted a policy in 2021 that allowed transgender women to compete if they maintained low testosterone levels, that policy has not been in effect since 2022, The Guardian reported last year. As of last summer, there were no known trans athletes in the NWSL.  

As the WTA takes this new step to enforce women players’ identities, advocacy groups say that gender testing is bad news for everyone. 

“Sex testing invades all women’s privacy, forcing them to surrender their personal medical and genetic information,” the intersex advocacy group interACT said in a statement. “All women, including trans and intersex women, deserve the chance to pursue their athletic dreams.”