Caster Semenya has lost her appeal against rules designed to decrease naturally high testosterone levels in some female runners. The Court of Arbitration for Sport said that rules on athletes with differences of sex development are discriminatory, but such discrimination is necessary to preserve the "integrity of female athletics".
Semenya, a two-time Olympic 800-metre champion, had requested to stop the introduction of regulations to limit testosterone in female athletes with differences in sexual development.
The International Assocation of Athletics Federations imposed regulations in November that would force "hyperandrogenic" athletes - those with "differences of sexual development" - to medically lower their testosterone levels to five nanomoles per litre of blood in order to compete as women.
After hearing a week of arguments in February, the panel of three judges at the Court of Arbitration for Sport in Lausanne, Switzerland, said on Wednesday that the IAAF's proposed rules are discriminatory. But in a 2-1 ruling, it said that "on the basis of the evidence submitted by the parties, such discrimination is a necessary, reasonable and proportionate means of achieving the IAAF's aim of preserving the integrity of female athletics in the Restricted Events."
Semenya remained silent throughout much of the proceedings. She has received support from many experts, who have argued that barring women with high testosterone levels from competition would be like excluding basketball players because they are too tall.
The United Nations Human Rights Council adopted a resolution last month, with unanimous support, calling the IAAF rules "unnecessary, humiliating and harmful". Her strongest support has come from South Africa, whose government has accused the IAAF of seeking to violate women's bodies whose testosterone levels are not public, will now be forced to medicate to suppress her testosterone levels if she wants to defend her world title in September in Doha, Qatar. The two women who finished behind her in the Rio Olympics 800m, Francine Niyonsaba and Margaret Wambui, have also faced questions about their testosterone levels.