Caster Semenya accuses IAAF of using her as a ‘guinea pig experiment’

Caster Semenya has accused athletics’ governing body of using her body “as a human guinea pig experiment” by forcing her to take medication to control her testosterone levels. The double Olympic 800m champion stepped up her attacks on the International Association of Athletics Federations after the court of arbitration for sport released its 163-page judgment explaining why it decided to rule against her in a landmark case last month.

Semenya is appealing against Cas’s decision, which requires athletes with differences in sexual development (DSD) to take hormone suppressants to lower their testosterone below five nmol/L if they want to compete internationally between 400m to a mile. And she made it quite clear that whatever happens she would never again take medication – something she was forced to do between 2010 and 2015.

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“The IAAF used me in the past as a human guinea pig to experiment with how the medication they required me to take would affect my testosterone levels,” she said. “Even though the hormonal drugs made me feel constantly sick, the IAAF now wants to enforce even stricter thresholds with unknown health consequences.

“I will not allow the IAAF to use me and my body again,” she added. “But I am concerned that other female athletes will feel compelled to let the IAAF drug them and test the effectiveness and negative health effects of different hormonal drugs. This cannot be allowed to happen.”

Among the revelations in Cas’s full report are that the IAAF did argue that Semenya – and other athletes with similar DSD conditions – should be regarded as “biological males”, which contradicts what the IAAF told the Guardian in February.

The full report also reveals that Semenya told the judges that testosterone-suppressing medication in the past had affected her mental and physical health, and in addition to the feeling of sickness she endured, “suffered from regular fevers and had constant internal abdominal pain”.

However, Cas also explains in more detail why it ruled in favour of the IAAF. It accepted that high testosterone in female athletes confers significant advantages in size, strength and power from puberty onwards and therefore ruled the policy was “necessary, reasonable and proportionate” to ensure fair competition in women’s sport.

In its decision it also said that 46 XY 5-ARD (5-alpha-reductase deficiency) athletes – such as Semenya – have “circulating testosterone at the level of the male 46 XY population and not at the level of the female 46 XX population. This gives 46 XY 5-ARD athletes a significant sporting advantage over 46 XX female athletes.”

The IAAF said it welcomed the publication of the report. “Having the arguments of all parties in the public domain will help to foster greater understanding of this complex issue,” it added. “Sport is one of only a few, narrow sectors of society in which biology has to trump gender identity to ensure fairness.”