On Wednesday, World Athletics (WA) made a major announcement: Beginning Sept. 1, all athletes looking to compete in the female category will be required to undergo a “once-in-a-lifetime” gene test to determine their biological sex.
The test will be conducted via a blood test or cheek swab and in place for the upcoming 2025 World Athletics Championships in Tokyo.
The process tests for the SRY gene, which is located on the Y chromosome and acts as the primary gene responsible for initiating male sex determination in mammals. The tests will determine whether an athlete may have transitioned to female after male puberty or possesses differences of sex development (DSD) that confer a testosterone-based performance advantage. These measures are designed to address concerns over fairness. If the gene is detected on an athlete’s test, they might not be eligible to compete.
The World Athletics Council has approved new regulations concerning eligibility conditions to compete in the female category for world ranking competitions.
The new regulations come into effect on 1 September 2025 and will be applied to the World Athletics Championships Tokyo 25… pic.twitter.com/BO8Lz4kfwS
— World Athletics (@WorldAthletics) July 30, 2025
“The philosophy that we hold dear in WA is the protection and the promotion of the integrity of women’s sport,” WA president Sebastian Coe said in the press release. “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. The test to confirm biological sex is a very important step in ensuring this is the case.”
The new regulations were first established in March to reaffirm its commitment to women’s sports and upholding the 2023 policy ruling that only biological female athletes may compete in the category. At the time, WA planned to implement the new testing rules for the 2025 championships, but still had to identifying testing providers, finalize procedures and determine a fair timeline.
“We are saying, at elite level, for you to compete in the female category, you have to be biologically female,” Coe continued. “It was always very clear to me and the WA council that gender cannot trump biology.”
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WA concludes the statement by insisting it “does not judge or question gender identity,” and “respects and preserves the dignity and privacy of individuals.”
The testing protocol will be overseen by member federations (i.e., Athletics Canada) as they prepare their athletes and teams for the World Championships in Tokyo. Athletics Canada sent out an email to athletes on Wednesday indicating that they will complete SRY-testing on female athletes at the 2025 Canadian Track and Field Championships.