Olympics committee affirms biology in eligibility rules

The International Olympic Committee (IOC) on Thursday published new guidelines for protecting women’s categories across all sports ahead of the 2028 Games in Los Angeles.

IOC President Kirsty Coventry said the policy is based on scientific evidence that clearly demonstrates male chromosomes give performance advantages in sports requiring strength, power, or endurance—putting women at a disadvantage if men compete against them. The policy only applies going forward and will not retroactively change the results of previous events where males won.

The 10-page policy requires a one-time cheek swab or blood test to screen for the presence or absence of the SRY gene in male DNA. Athletes with differences/disorders in sexual development, or DSD, that give them bodies that appear female but have male chromosomes will only qualify for male category sports.

Why did the IOC create this policy? The IOC has previously deferred to the governing bodies of each sport to determine eligibility rules. In 2021, it released a now defunct policy encouraging international federations to prioritize inclusion and nondiscrimination when determining eligibility.

During the 2024 summer Olympics in Paris, the IOC allowed two boxers who previously failed female eligibility tests required by the International Boxing Association to compete in the women’s category.

Then in February 2025, U.S. President Donald Trump ordered Secretary of State Marco Rubio to work with the IOC on amending its eligibility guidelines to ensure participation is based on sex, rather than gender identity or testosterone reduction. One month later, Coventry, a gold medal swimmer from Zimbabwe, took the helm at the IOC. In June, she launched a working group to focus on protecting women’s sports categories.

Dig deeper: Read Juliana Chan Erickson’s report on legal cases about women’s sports in the U.S.