The International Olympic Committee (IOC) announced on Thursday that from now on women will be required to undergo DNA testing. Only athletes who do not carry a Y chromosome will be eligible to compete in women’s categories, with an exception for those diagnosed with disorders of sex development-for example, androgen insensitivity syndrome, where the body does not respond to testosterone.
IOC president Kirsty Coventry said it is obvious that it would be “unfair” to allow biological men to compete in the women’s division, and that in some sports it would be “simply unsafe”.
Sex‑testing debates in sport date back to the 1940s. At the 1966 European Athletics Championships, women had to undress before a panel of doctors and have their genitals examined. In 1967 the IOC introduced a rule that used a mouth swab to determine a person’s chromosomes. That same year Polish athlete and Olympic champion Ewa Klobukowska was barred from the women’s category after a Y chromosome was detected; she later gave birth to a son the next year.
The 1990s saw a shift from mouth swabs to DNA tests in suspected cases. Transgender individuals were required to undergo sex‑reassignment surgery. In 2011 the governing body for athletics (IAAF) switched to testosterone testing, because a genetic “blueprint” does not set physical development for everyone. The new regulation sometimes forced healthy women to take hormone blockers to lower naturally high testosterone levels.