Faced with growing pushback, the international track federation is standing behind a new eligibility rule that defines female athletes by their body chemistry.
The IAAF has sought to bar from competition any women with naturally high testosterone levels unless they agree to run against men or take medication to reduce those levels.
Two U.S.-based organizations — the Women’s Sports Foundation and Athlete Ally — have publicly opposed the regulation, which is scheduled to take effect Nov. 1.
“No woman should be required to change her body to compete in women’s sport,” Athlete Ally stated.
Track officials responded with an open letter Tuesday, writing: “The IAAF has been a leading supporter of women in sport for most of its long history and will continue to be.”
The issue focuses on athletes with a “difference of sexual development” or DSD — meaning they have a circulating level of testosterone at five nanomoles per liter or greater and are androgen-sensitive.
Believing that such athletes hold an unfair advantage, the federation has aimed its rule at all races between 400 meters and the mile, which could present a challenge for South African runner Caster Semenya, the reigning Olympic champion who has long dominated at 800 meters.