Less than a week after sports' highest body ruled that Olympian Caster Semenya must take drugs to suppress her testosterone levels to compete in certain women's races, she has been told, however, she can compete with men in “any competition at any level” and “without restriction."

The letter was published this week by the International Association of Athletic Federations, track and field’s international governing body. It comes on the heels of the landmark ruling in IAAF’s favor by the Court of Arbitration for Sport in Switzerland, the highest court in international sports, about Semenya, a South African track champion.

The IAAF’s letter was addressed to the World Medical Association, which had strongly urged “physicians around the world to take no part in implementing” the federation’s controversial rules for classifying female athletes. As is the case with Semenya, the new regulations require women athletes with relatively high levels of testosterone to medically reduce their natural blood testosterone level if they want to continue competing as women in certain events.

“The IAAF has implemented what might be called ‘sexual eugenics,’” Roger Pielke Jr., director of the Sports Governance Center at the University of Colorado, said.

“It has concluded that some females are not female enough because of their genetics and must be improved through medication,” he added. “It is deeply troubling and unethical.”

In its letter to the World Medical Association, which also questioned the “ethical validity” of the new “Differences of Sex Development” regulations, the IAAF defended itself and sought to clarify its position.

“The IAAF Regulations in this matter are not based on a single study, but on many scientific publications and observations from the field during the last 15 years,” the letter, signed by three IAAF-affiliated physicians, stated. “All these materials were submitted to the Court of Arbitration for Sport and discussed during the hearing. The Panel has accepted the validity of this evidence and has recently decided to uphold the IAAF Regulations.”

The Court of Arbitration for Sport in Switzerland, the highest court in international sports, last week upheld the IAAF's standards dictating and regulating who can compete in women's sports. While the court conceded the IAAF’s policy is “discriminatory” to athletes with “differences in sexual development” (DSD), such as Semenya, it found that “such discrimination is a necessary, reasonable and proportionate means of achieving the legitimate objective of ensuring fair competition in female athletics.”

The court’s ruling is expected to have widespread implications for transgender and intersex athletes throughout sport and has been criticized by some supporters of Semenya as sexist and racist.

“The IAAF's policy is a horrific violation of female athletes everywhere; no woman should have to undergo medically unnecessary intervention in order to compete in women's sport,” said Anne Lieberman, director of policy and programs at Athlete Ally, an advocacy group which encourages LGBTQ representation and acceptance in sports.

Semenya has said that she does not want to move forward with the medical interventions required by the IAAF.

“These interventions are being mandated for eligibility, not health, and thus they are medically unnecessary, coercive, and violate bodily autonomy and integrity,” said Katrina Karkazis, bioethicist at Yale University who consulted with Semenya’s team prior to the hearing in the Swiss court.

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