Double Olympic champion Caster Semenya said she offered to show her vagina to athletics officials when she was just 18 years old to prove she was a female.
In an interview with HBO Real Sports, she also accused track and field's world governing body of making her take medication if she wanted to compete that "tortured" her and left her fearing she was going to have a heart attack.
In the interview, Semenya reflected on the 2009 world championships in Berlin, where she won the 800-mete title in dominant fashion as an 18-year-old newcomer at her first major international meet.
But her performance and muscular physique led the sport's governing body to insist the teenager undergo sex tests, causing a firestorm of controversy.
Semenya said track officials from the governing body "probably" thought she had a penis.
"I told them, 'It's fine. I'm a female. I don't care. If you want to see I'm a woman, I will show you my vagina. Alright?'"
Following her world title win, Semenya was forced by the international athletics federation to take medication that artificially lowered her naturally high testosterone if she wanted to compete against other female runners.
Although the world track body has never released details of Semenya's specific medication, it's believed she took birth control pills or something with similar properties to lower her testosterone.
"It made me sick, made me gain weight, panic attacks. I didn't know if I was ever going to have a heart attack," Semenya said of the medication.
Australian Associated Press
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