Caster Semenya flexing
Caster Semenya of South Africa celebrates wins gold in the Women's 800 metres final during athletics on day nine of the Gold Coast 2018 Commonwealth Games at Carrara Stadium on April 13, 2018 on the Gold Coast, Australia. (Photo by Michael Dodge/Getty Images)
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Swiss court says Caster Semenya can run

Caster Semenya flexing
Caster Semenya of South Africa has been allowed to compete in any race without having to take testosterone-reducing medication according to a temporary ruling issued by Switzerland's top court.   (Photo by Michael Dodge/Getty Images)

A Swiss court has temporarily suspended an International Association of Athletics Federation rule that would have forced  South African gold medalist Caster Semenya to take testosterone-reducing medication in order to compete.

Black text that reads why this matters
By making intersex and DSD middle-distance runners comply with new regulations, the IAAF is singling out only a small portion of competitors in an effort to legislate fairness.

Semenya had appealed the IAAF's decision to the Court of Arbitration for Sport, which upheld the initial ruling, forcing Semenya and other female middle-distance runners who had higher levels of testosterone to take testosterone-reducing medication. Semenya then appealed the CAS ruling to the Swiss Federal Tribunal, Switzerland's supreme court. CAS is located in Switzerland.

"I am thankful to the Swiss judges for this decision," Semenya said in a statement.

Under the IAAF rules, Semenya would not have been allowed to run in international races from 400m to the mile unless she medically reduces her natural testosterone levels for six months.

In a statement to BBC Sport, the tribunal said it had "super-provisionally instructed the IAAF to suspend the application of the 'Eligibility Regulations for the Female Classification for athletes with differences of sex development' with respect to the claimant, until the decision on the request for issuance of provisional measures."

"At present, it is not known when the Swiss Federal Supreme Courts will issue an interlocutory order concerning these provisional measures."

Semenya's legal representative Dorothee Schramm said in a statement:  "The court has granted welcome temporary protection to Caster Semenya.

"This is an important case that will have fundamental implications for the human rights of female athletes."

“I am a woman and I am a world-class athlete,” she said in a statement at the time of her appeal in May. “The IAAF will not drug me or stop me from being who I am.”

CAS ruled on May 1 that Semenya must comply with the new levels if she wants to compete against other women in international competitions.

CAS threw out Semenya's appeal against the IAAF despite saying they had "serious concerns as to future practical application."

That ruling stated that after May 8, athletes with differences of sexual development (DSD) needed to take a blood test to monitor their testosterone levels. This is the only way to maintain their eligibility for the IAAF World Championships in September or the Tokyo Olympics in 2020.

Arbitrators took more than two months to deliberate the initial case. According to The Guardian, two of the three arbitrators agreed with the IAAF's argument that high testosterone in females gives an advantage in size, strength and power after puberty, and that the new policy "was necessary, reasonable and appropriate" to ensure fair competition.

“I know that the IAAF’s regulations have always targeted me specifically,” Semenya told The Guardian.  “For a decade the IAAF has tried to slow me down, but this has actually made me stronger. The decision of the CAS will not hold me back. I will once again rise above and continue to inspire young women and athletes in South Africa and around the world.”

In a statement about the decision, CAS said:  “The panel found that the DSD Regulations are discriminatory but 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.”

However, CAS did share concerns about the ruling, singling out fairness, difficulty implementing and complying with the ruling, no real evidence to include certain events — specifically middle distance races—and the potential health risks for athletes forced to comply with the medical requirements.

On the health issues, CAS  added: “The side effects of hormonal treatment, experienced by individual athletes could, with further evidence, demonstrate the practical impossibility of compliance which could, in turn, lead to a different conclusion as to the proportionality of the DSD regulations.”

According to The Guardian, a spokesperson for Semenya said: “Ms Semenya believes that the dissenting CAS arbitrator will be shown to be correct and the DSD Regulations will be overturned.”

“In the interim, Ms Semenya believes that it is irresponsible for the IAAF to proceed with the implementation of the DSD Regulations in circumstances where the CAS decision makes it abundantly clear that there are serious problems with the regulations that need to be carefully considered and the DSD Regulations will unquestionably cause harm to the women affected by them.”


Semenya has hyperandrogenism. According to the American Association of Clinical Endocrinologists, it is a condition in which the female body produces abnormally high levels of testosterone.

In 2018, the International Association of Athletics Federation (IAAF) created new eligibility regulations for women with Differences of Sexual Development (DSD). DSD athletes have testosterone levels of 5 nanomoles per liter (nmol/L) or above. The regulations state that if the athletes want to continue competing as women in hurdles, the 400 meter, 800 meter, 1500 meter and mile races then they must lower their levels below 5 nmol/L.

The IAAF defined normal female testosterone levels are between 0.12 and 1.79 nmol/L, whilemale testosterone levels are between 7.7 and 29.4 nmol/L.

In order to lower their testosterone levels to compete, athletes must use a hormonal contraceptive to lower their levels below 5 nmol/L for at least six months. After the six months, athletes must keep stay below that level for as long as they compete. They must also be recognized as female or intersex.

When the IAAF released the regulations, some experts were puzzled by the testosterone levels the IAAF deemed as normal. According to Alina Health, the average testosterone levels for women are between 0.52 and 2.43 nmol/L. The average levels in men are between 10.41 and 34.70 2.43 nmol/L. Those levels are different from the IAAF’s levels.

In response to the new regulations, Semenya and Athletics South Africa protested to the Court of Arbitration for Sport.

“I am very upset that I have been pushed into the public spotlight again; I don’t like talking about this new rule,” Semenya said in a release. “I just want to run naturally, the way I was born.”

In 2009, Semenya underwent sex determination testing by the IAAF after she won gold in the women’s 800 meter race at the world track and field championships in Berlin.

Although the testing was supposed to be confidential, reports leaked that her testosterone levels were three times higher than the average for women. The IAAF suspended her for 11 months while medical experts reviewed her case.

Three independent researchers found flaws in the data used to create the new DSD regulations.

The data comes from a 2017 study, which used results from the 2011 and 2013 world track and field championships. The study reported women with very high testosterone levels significantly outperformed women with lower testosterone levels in the 400 meter hurdles, 400 meter and 800 meter races.

“They cannot use this study as an excuse or a reason for setting a testosterone level because the data they have presented is not solid,” researcher Erik Boye said.

Ross Tucker, a professor of exercise physiology at the University of the Free State in South Africa, who said he believes biology is the main problem, and that testosterone is the main reason men have an athletic advantage over women.

“That’s basically the crux of the issue,” Tucker said.  “Do intersex athletes who compete as females have an advantage thanks to testosterone that is unfair, even compared to obviously other recognized advantages in sport?”

Tucker thinks so.

Paula Radcliffe, a marathon world record holder, opposes Semenya competing in women’s sports. She believes that Semenya’s 800 meter dominance is “no longer sport.”

“Girls on the start line know they’re never going to get a medal in an 800m. That’s the bottom line. I get really annoyed when I see these arguments come back that it’s racist or it’s sexist. It’s none of those,” Radcliffe said.

Editor’s note: For the coming 2019-2020 academic year, the Global Sport Institute’s research theme will be “Sport and the body.” The Institute will conduct and fund research and host events that will explore a myriad of topics related to the body.

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