To ensure fair competition, WA introduced new regulations effective 1/9. These regulations, implemented at the World Athletics Championships in Tokyo, Japan, starting 13/9, require a one-time test for the SRY gene, a marker for biological males. The test involves a buccal swab or blood sample.

WA stated that member federations will oversee the testing process before each event. All selected athletes must complete the test before 1/9.

Dr. Stephane Bermon, head of health and science at World Athletics.

Dr. Stephane Bermon, WA's head of health and science, detailed the participation of DSD athletes in top-level athletics during a presentation. "Sex testing is necessary due to the overrepresentation of DSD athletes in finals," he said.

In legal battles with the Court of Arbitration for Sport, WA argued that DSD athletes are 140 times more prevalent in athletics than in the general population. Bermon's Tokyo presentation placed that estimate even higher, at 151.9 times.

From 2000 to 2023, Bermon reported 135 DSD athletes reached finals in major international competitions, with some competing in multiple finals. DSD athletes are biological males with a full 46 XY chromosomes but "ambiguous genitalia" and "some atypical internal structures". They are often assigned female at birth, frequently in less developed countries.

Prominent athletes like South Africa's Caster Semenya, a two-time Olympic 800m gold medalist (2012 and 2016), and Namibia's Christine Mboma, the 200m silver medalist at the 2020 Olympics, face exclusion under the new rules unless they undergo testosterone suppression therapy.

WA's data, derived from anti-doping tests revealing high testosterone levels, triggers additional testing. Dr. Bermon emphasized WA's leading role in this area, with president Lord Coe committed to protecting women's categories.

Caster Semenya, a two-time Olympic 800m gold medalist, is one of the most controversial female athletes.

DSD athletes identified before 1/9, under the 2023 regulations, must maintain testosterone levels below 2.5 nmol/L. They can compete but with restrictions for the rest of their careers.

WA stated similar regulations for transgender athletes are currently unnecessary, as none compete at the highest level. However, future regulations may combine DSD and transgender policies.

When announcing the new sex determination method, WA President Lord Coe stressed: "Our philosophy is to protect and promote fairness in women's sports. In a sport striving to attract more women, it's crucial they compete confidently, knowing there are no biological advantages. Biological sex testing is essential for this." He added, "At the highest level, to compete in women's events, athletes must be biologically female. For me and WA, social gender cannot supersede biological sex."

Hoang Thong (according to The Times)