Before the hearing, Semenya’s lawyers and Athletics South Africa (ASA) accused the IAAF of breaching confidentiality regulations by releasing a list of five expert witnesses who will testify on its behalf.
Under the IAAF rule, female athletes with naturally high testosterone levels would have to race against men or change events unless they took medication to reduce it.
Athletes who wanted to compete in those events must take medication for six months, then maintain a lower testosterone level.
The two-times Olympic 800m champion is challenging the introduction of revised eligibility rules for athletes with disorders of sexual development in a case that could have enormous implications.
It was intended the new rule would be brought in on November 1st last year but the legal challenge from Semenya and ASA prompted that to be delayed until 26 March.
Semenya’s lawyer said that Semenya believes the IAAF press release is a clear breach of the confidentiality provisions that was orchestrated in an effort to influence public opinion in circumstances where the IAAF knew that Semenya would not be prepared to respond because she was complying with her confidentiality obligations.
The silver and bronze medallists in the Rio Olympics 800m, Francine Niyonsaba of Burundi and Kenya’s Margaret Wambui are also among those to be questioned.