Caster Semenya
South African Olympic 800m champion Caster Semenya looks on after running the 1.500m senior women final at the ASA Senior Championships at Germiston Athletics stadium, in Germiston on the outskirts of Johannesburg, South Africa on April 26, 2019. (Photo by STRINGER / AFP) (Photo credit should read STRINGER/AFP/Getty Images)
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Court rules Semenya must comply with IAAF testosterone regulations

Kathy Kudravi and Katelyn Oates |
Caster Semenya
South African Olympic 800m champion Caster Semenya looks on after running the 1.500m senior women final at the ASA Senior Championships at Germiston Athletics stadium, in Germiston on the outskirts of Johannesburg, South Africa on April 26, 2019. (Photo by  STRINGER/AFP/Getty Images)

The Court of Arbitration for Sport has ruled that South African middle-distance champion Caster Semenya must comply with  the governing body of track and field and take medication to reduce her testosterone levels if she wants to compete against other women in international competitions.

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.

CAS threw out Semenya's appeal against the International Association of Athletics Federation despite saying they had "serious concerns as to future practical application."

Beginning May 8, athletes with differences of sexual development (DSD) will need 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 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.

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