A27. Intersex conditions result from differences in biological sex development. They are also known as differences of sex development or DSDs. There are many different intersex conditions, but those that are relevant for sport all involve biological males – individuals with an XY karyotype, testes, and testosterone levels in the male range – whose sex development was atypical in some respect. For example, their external genitalia might not be fully formed or their androgen receptors may be less than typically sensitive. Athletes with such intersex conditions may be raised as male or female. People who are transgender do not generally consider themselves to be intersex. The two are related in sport to the extent that they may both involve biological males with full or partial male advantage who seek eligibility to compete in girls’/women’s sport competition.
The following table is illustrative. It is from an exhibit in the case brought by South African runner Caster Semenya against her international federation (the IAAF now World Athletics) at the Court of Arbitration for Sport (CAS) in Switzerland. Semenya is sometimes described as intersex. In 2019, CAS upheld the federation’s eligibility rules for the women’s category. Those rules require affected athletes to verifiably reduce their testosterone levels to within the normal female range for a 12-month period before they can compete in that category. Switzerland’s Supreme Court affirmed the CAS decision in 2020.
COMPARING BIOLOGICAL SEX TRAITS FOR PURPOSES OF GIRLS’ AND WOMEN’S SPORT (from IAAF Exhibit in Semenya and ASA v. IAAF)
Note: MTF = Male to Female