LONDON: Female athletes with excessive levels of male hormones will require medical clearance to compete in women's events under new rules adopted Tuesday by track and field's governing body. The IAAF became the first international sports federation Tuesday to approve new rules on the eligibility of female athletes with “hyperandrogenism” – a condition involving overproduction of male sex hormones. The rules are intended to avoid any repeat of the controversy which surrounded South African runner Caster Semenya, who was ordered to undergo gender verification tests and was sidelined for 11 months after winning the 800-meter world title in 2009. The IAAF worked with the International Olympic Committee, which agreed last week to adopt new rules and urged all sports federations to enact similar measures. The IAAF council, meeting in the South Korean city of Daegu that will host this year's world championships, said the rules will go into effect on May 1. The rules are based on the grounds that the difference between sporting performance between elite men and women is “predominantly due to higher levels of androgenic hormones in men.” Women with hyperandrogenism will be eligible to compete in female competition if their androgen levels are below the men's range or, if within the male range, they have an androgen resistance which means they derive no competitive advantage, the IAAF said. Otherwise, they will not be eligible for women's events. The IAAF said it has appointed a panel of international medical experts to review any hyperandrogenism cases. The panel will make recommendations on eligibility to the IAAF. The process may include referring an athlete “for full examination and diagnosis with best medical practice” at one of six IAAF-approved specialist centers around the world. The process will be conducted “in strict confidentiality” and cases referred to the panel on an anonymous basis. Any female athlete who declines, fails or refuses to comply with the eligibility process will be ineligible to compete in women's events, the IAAF said. The federation said it has also modified its existing rules on participation in women's competition of athletes who have undergone male to female sex reassignment. The issue of female eligibility gained global attention after Semenya dominated the women's 800 meters at the 2009 worlds in Berlin. Her dramatic improvement in times and muscular build led the IAAF to order gender tests. Amid acrimony between the IAAF and Semenya and South African officials, the case dragged on for 11 months before the IAAF cleared Semenya to run again last July. The IAAF has refused to confirm or deny Australian media reports that tests indicated Semenya had both male and female sex organs.