Track and field’s global governing body, World Athletics, has moved to require a one-time genetic test for all female athletes competing at world-ranking events. The test checks for the presence of the SRY gene, which is found on the Y chromosome and triggers male biological development. If an athlete tests positive, she cannot compete in the female category.
The rule came into effect on September 1, 2025, ahead of the World Athletics Championships in Tokyo, which opened on September 13. The decision represents the most significant update to World Athletics female athlete eligibility rules in years, going further than earlier testosterone-based thresholds that had defined the debate since at least 2019.
What Is the SRY Gene Test and How Is It Done
The SRY gene test is not invasive and does not need to be repeated. Athletes can provide a cheek swab or a dry blood-spot sample. Their national federation oversees the process, and the test only needs to happen once across an athlete’s entire career.
The test checks whether someone has transitioned to a female after going through male puberty or whether they have differences of sex development that provided testosterone advantages. According to BBC reporting, the test looks specifically for the SRY gene, which is part of the Y chromosome and causes male characteristics to develop.
The simplicity of the process is deliberate. World Athletics wanted a method that was practical for member federations around the world to implement before a major championship deadline.
Why World Athletics Changed Its Approach
The shift from testosterone thresholds to genetic testing did not happen overnight. For years, the governing body’s female athlete eligibility framework centered on testosterone levels in the blood specifically targeting athletes with Differences of Sex Development (DSD).
Earlier regulations required any athlete with a DSD condition whose circulating testosterone reached 5 nmol/L or above, and who was androgen-sensitive, to reduce her testosterone to below 5 nmol/L for a continuous period of at least six months before competing in restricted events. Those rules applied to specific middle-distance and sprint events where testosterone was found to offer the most measurable performance advantage.
The female athlete eligibility rules in 2021 were updated with endorsement from an international panel of medical experts. The 2021 regulations, approved by Council on 30 November 2021 and effective from 10 December 2021, maintained the core framework around testosterone suppression while incorporating updated medical guidance. Female athlete eligibility in 2022 continued under those same rules, with testosterone testing remaining the primary mechanism.
But critics of the testosterone-based approach argued it was both medically invasive and difficult to enforce consistently. The move to genetic testing is an attempt to create a more definitive and standardized method.
Sebastian Coe’s Statement on the New Rules
World Athletics President Sebastian Coe has been direct about the reasoning behind the decision. Coe said: “The philosophy that we hold dear in World Athletics is the protection and the promotion of the integrity of women’s 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. The test to confirm biological sex is a very important step in ensuring this is the case.”
He has also said that at the elite international level, World Athletics wants female athletes to be biologically female to compete in the women’s category. The phrase “no biological glass ceiling” has since been widely quoted in coverage of the policy.
Who Is Affected and Who Is Not
The new framework under Rule 3.5.2 of the World Athletics Eligibility Rules sets out clearly who can compete in the female category.
Only the following athletes may compete in the female category: biological females with no Y chromosome, irrespective of legal sex or gender identity. Biological females who have used testosterone as part of male gender-affirming treatment may not compete in the female category until a period of at least four years has passed after their last use of testosterone. Biological males with Complete Androgen Insensitivity Syndrome, who have not gone through male sexual development or male puberty, are also eligible.
Transgender women are not covered by transitional provisions because, according to World Athletics, none are currently competing at the elite international level under existing rules.
The question of whether female athletes have higher levels of testosterone than the general female population is relevant here. Most female athletes, including elite competitors, naturally have testosterone levels between 0.12 and 1.79 nmol/L. The normal range of serum testosterone levels in men is 7.7 to 29.4 nmol/L. Athletes with certain DSD conditions can have levels significantly above the typical female range while still being below the male range which is why the earlier testosterone-based rules were so contested.
The Caster Semenya Case Still Unresolved
No discussion of World Athletics female athlete eligibility is complete without reference to South African middle-distance runner Caster Semenya, who has been at the center of this debate since she won her first 800m world title as a teenager in 2009.
In July 2025, the European Court of Human Rights ruled that the Swiss Federal Supreme Court had violated Semenya’s right to a fair hearing when it rejected her 2020 appeal against World Athletics regulations requiring DSD athletes to reduce their testosterone levels. That legal win did not overturn athletics’ eligibility rules it addressed Switzerland’s handling of her case, not World Athletics directly.
Her case has shaped nearly every version of the female athlete eligibility framework. The 2019 regulations, the 2021 update, the 2022 enforcement period all of them carried the shadow of her legal challenges. The new genetic testing policy does not resolve her situation either.
How Other Sports Are Responding
World Athletics is not alone in tightening eligibility rules. Algerian boxer Imane Khelif has filed an appeal before the Court of Arbitration for Sport against World Boxing’s decision to introduce mandatory sex testing as part of its new eligibility policy. Tennis has also entered this territory.
Women’s tennis players are now required to take a one-time gene test for eligibility under new sport-specific rules. The spread of genetic testing policies across different sports suggests this is becoming a broader trend rather than a decision unique to track and field.
USA Track and Field has confirmed it follows World Athletics policy, meaning the SRY gene testing requirement applies to American athletes competing in World Athletics-certified events as well.
What the World Athletics Testosterone Regulations Have Always Been Trying to Solve
The World Athletics testosterone regulations, across every version from 2019 through 2025, have tried to answer one core question: does naturally elevated testosterone in female athletes give them a competitive advantage that goes beyond what training, genetics, and talent can explain?
The governing body’s position has consistently been yes at least in certain events. World Athletics has argued that because of the effect of testosterone on the body from puberty onwards, men are bigger, stronger, and faster on average than women, which is why the female classification is protected.
The shift to the SRY gene test moves the question from hormone levels in the blood to chromosomal biology. It is a harder line, and it removes the case-by-case medical flexibility that characterized the earlier DSD framework. Whether that is better or fairer is something sports scientists, lawyers, and athletes continue to disagree on.
Global Impact of the New Policy
The introduction of genetic testing for female athlete eligibility has drawn attention far beyond the athletics track. Advocacy groups for intersex and transgender athletes have criticized the policy as medically reductive. Sports administrators in other disciplines are watching closely.
A majority of World Athletics stakeholders agreed with the position that ensuring only biological females compete in the female category is necessary for the integrity of women’s sport. But opponents argue that reducing eligibility to a single gene test ignores the medical complexity of sex development and may push athletes with natural hormonal differences out of the sport entirely.
The case of Christine Mboma of Namibia is often cited. She set a world under-20 record in the 200m at the Tokyo Olympics in 2021 after being excluded from her preferred 400m event due to DSD regulations. Her situation illustrated how the rules can affect young athletes who have never taken any performance-enhancing substance.
What Comes Next
The September 2025 World Championships in Tokyo were the first major event held under the new SRY gene testing requirement. How the policy plays out in practice particularly for athletes who test positive and face exclusion from competition is expected to generate further legal challenges.
The Court of Arbitration for Sport has become the primary venue for disputes over eligibility rules in athletics, and more cases are likely. World Athletics has said it will continue reviewing its regulations, but the current policy direction is clearly toward biological sex as the defining criterion for female category competition.
How women’s sports handle these questions over the next few years will matter well beyond athletics. The decisions made now are setting precedents that other governing bodies are already borrowing from.
FAQs
Is there a testosterone limit for female athletes?
Yes, there is though the specific threshold has changed over the years and now applies alongside genetic testing. Under earlier World Athletics regulations, female athletes with Differences of Sex Development who had naturally elevated testosterone were required to reduce their levels to below 5 nmol/L for at least six months before competing in certain restricted events, such as the 400m, 800m, and related distances. That threshold was set partly in reference to women with polycystic ovary syndrome, whose testosterone levels can reach up to around 3.1 to 4.8 nmol/L at the higher end, well below the typical male range of 7.7 to 29.4 nmol/L. The newer 2025 framework moves the primary eligibility criterion to genetic testing specifically the absence of the SRY gene rather than relying solely on testosterone suppression. So while testosterone remains scientifically relevant to the debate, the current binding rule for female athlete eligibility focuses on chromosomal biology rather than hormone levels alone.
What are the requirements for being an athlete in the female category under World Athletics rules?
Under the rules effective from September 1, 2025, an athlete must be a biological female with no Y chromosome to compete in the female category at world-ranking events. This is confirmed through a one-time genetic test either a cheek swab or a dry blood-spot sample — administered by the athlete’s national federation. Biological females who have used testosterone as part of male gender-affirming treatment are excluded from the female category for a minimum of four years after their last use, with the exact period determined on a case-by-case basis depending on the timing, dosage, duration, and effects of the treatment. Biological males with Complete Androgen Insensitivity Syndrome, who have not undergone male puberty or male sexual development, may also be eligible under specific provisions. The test is a one-lifetime requirement once cleared, an athlete does not need to repeat it.
What is the gender eligibility test in athletics?
The gender eligibility test now used by World Athletics is the SRY gene test. The SRY gene sits on the Y chromosome and is responsible for triggering male biological development during embryonic development. If this gene is detected in an athlete’s sample, she is ineligible to compete in the female category at elite events governed by World Athletics. The test itself is non-invasive and quick it uses a cheek swab or a dry blood-spot card, the kind of low-tech method familiar from medical screening programs. This is distinct from earlier approaches that relied on testosterone blood testing, which required ongoing monitoring and periodic retesting. The SRY gene test is intended to be administered once and never needs to be repeated, making it simpler to manage for both athletes and national federations. It is already being adopted in other sports, including women’s tennis, as governing bodies across disciplines align on a chromosomal standard for female category eligibility.
