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.