By Ben Traynor | Runner’s Tribe | July 31, 2025
In a landmark policy shift, World Athletics has announced that all female track and field athletes will be required to undergo a once-in-a-lifetime genetic test to confirm their biological sex in order to compete in world-ranking competitions. The rule comes into effect on September 1, 2025, just days before the start of the World Athletics Championships in Tokyo, which begin on September 13.
The new regulation mandates a test for the SRY gene, which determines the presence of a Y chromosome an indicator of male biological sex. The test, which can be administered via cheek swab or blood sample, is intended to verify whether an athlete is biologically female. If confirmed, the athlete will not need to be tested again.
According to World Athletics, the policy is aimed at reinforcing the integrity of the women’s category at the elite level. The organisation’s president, Sebastian Coe, said the decision was driven by a need to protect the fairness of female sport.
“It is really important in a sport that is permanently trying to attract more women that they enter a sport believing there is no biological glass ceiling,” Coe said. “The test to confirm biological sex is a very important step in ensuring this is the case.”
“At elite level, for you to compete in the female category, you have to be biologically female. It was always very clear to me and the World Athletics Council that gender cannot trump biology.”
The new rule follows recent moves by other sports governing bodies. In May, World Boxing introduced mandatory sex testing for its amateur athletes. Earlier this month, the US Olympic and Paralympic Committee also updated its eligibility standards, aligning with a federal executive order that bars transgender women from competing in female categories.
The regulation was shaped by recommendations from World Athletics’ Gender Diverse Athlete Working Group, which concluded earlier this year that existing eligibility standards primarily based on testosterone levels did not sufficiently address the complexity of sex classification in elite sport. The SRY gene test was one of several recommended updates.
Female athletes whose tests detect the presence of Y chromosomes will not be permitted to compete in the women’s category. World Athletics has described the SRY gene test as “highly reliable,” with minimal room for error.
Caster Semenya and the Wider Debate
The announcement arrives against a backdrop of ongoing legal and ethical debate surrounding gender and sex in sport. Earlier this month, the European Court of Human Rights ruled that two-time Olympic 800m champion Caster Semenya was denied a fair legal hearing in her appeal against World Athletics’ regulations requiring DSD (differences of sexual development) athletes to lower their testosterone levels to compete.
Semenya, who has naturally elevated testosterone and has refused to undergo medical treatment to lower it, has been effectively barred from elite-level competition since 2019. While the court’s ruling may allow her case to return to Swiss courts, it does not currently affect World Athletics’ eligibility rules.
World Athletics maintains that its position is not intended to exclude but to preserve a level playing field.
“We particularly want to thank our Member Federations for their support and commitment in the implementation of these new regulations,” Coe said.
With the Tokyo World Championships just weeks away, national federations have been tasked with overseeing the implementation of the testing protocols as part of athlete preparation.
The introduction of genetic testing represents a significant tightening of the criteria for competing in female events, replacing past policies that relied primarily on hormonal thresholds. As the athletics world prepares for one of its biggest events of the year, the move signals a definitive stance from the sport’s highest authority, one that will continue to provoke both support and scrutiny in equal measure.
