What Happened to Gender Verification in Sports?

Gender verification in sports has a long and often controversial history, initially emerging in the 1940s with rudimentary "femininity certificates" and evolving through various methods to address concerns about competitive fairness in women's events. Early practices included visual inspections and physical examinations, which were highly invasive and demeaning. By the 1960s, formal sex verification became a requirement, driven partly by concerns over doping and the perceived blurring of physical differences between male and female athletes. From 1968 to 1998, the International Olympic Committee (IOC) mandated chromosome testing for all female athletes, a practice that was eventually abandoned due to its unreliability and discriminatory impact, particularly on intersex individuals.

The early 21st century saw a move away from universal testing towards a focus on testosterone levels, particularly for athletes with Differences of Sex Development (DSD) and transgender women. The IOC's 2003 guidelines for transgender athletes required gender reassignment surgery and two years of hormone therapy, later revised in 2015 to remove the surgery requirement and focus on testosterone suppression. However, these policies remained contentious, notably highlighted by the ongoing legal battles of South African runner Caster Semenya, an intersex athlete whose naturally high testosterone levels led to her exclusion from certain events unless she underwent hormone-suppressing treatment. Her case brought significant international attention to the human rights implications of such regulations.

A significant turning point occurred in 2021 when the IOC shifted its stance, issuing a framework that recommended individual sports federations develop their own eligibility criteria, moving away from a universal testosterone limit. However, this period of decentralization proved short-lived. In 2025 and 2026, there has been a pronounced global trend back towards stricter, biologically-defined categories. World Athletics, the governing body for track and field, implemented new regulations on September 1, 2025, requiring a one-time SRY gene test for all athletes wishing to compete in the female category at elite levels. This policy effectively prohibits female athletes with a Y chromosome from competing in women's events.

Further solidifying this shift, the IOC announced a new policy on March 26, 2026, for the protection of the female category in Olympic sports. This policy mandates that eligibility for any female category event at the Olympic Games, starting with LA28, is limited to "biological females" as determined by a one-time SRY gene screening. This move has been widely criticized by human rights organizations and advocates for transgender and intersex athletes, who argue it is discriminatory, invasive, and a significant setback for inclusion. Concurrently, in the United States, the Supreme Court upheld Idaho's "Fairness in Women's Sports Act" in June 2026, allowing states to restrict transgender women and girls from competing on women's sports teams based on biological sex. Many national sports federations in the US and other countries have also updated their policies in 2025-2026 to align with these biological sex-based criteria, reflecting a global re-evaluation of gender eligibility in competitive sports.