The International Olympic Committee has said it will reintroduce genetic gender testing to determine eligibility for female events at the 2028 Los Angeles Games and beyond.

The International Olympic Committee (IOC) said on Thursday that it would reintroduce genetic gender testing to determine eligibility for female events at the 2028 Los Angeles Olympic Games.

"Eligibility for any female category event at the Olympic Games or any other IOC event, including individual and team sports, is now limited to biological females, determined on the basis of a one time gene screening," the committee said following an 18-month consultation.

"Based on scientific evidence, the IOC considers that the presence ​of the SRY gene is fixed throughout life and represents highly accurate evidence that an athlete has experienced male sex development," the IOC said.

Olympic Controversies over Transgender Athletes

The announcement sees the IOC abandoning previous rules introduced in 2021, which allowed individual federations to decide their own policy in favor of a policy implemented across all sports.

The IOC announced the policy as part of its initiative ‌to introduce a ⁠universal ⁠rule for competitors in female elite sports after years of fragmented regulations sparked several controversies.

At the Paris Olympics in 2024, boxers Imane Khelif of Algeria and Lin Yu-ting of Taiwan won gold medals a year after they were disqualified from the world championships, which is run by the International Boxing Federation (IBA), after allegedly failing eligibility tests.

But the IOC, which has run the last two Olympic boxing tournaments because it has suspended IBA for various other reasons, said Khelif and Lin could compete because they were born as and identify as women.

The new rule, which the IOC said applies to its elite Olympic events but not recreational or grassroots sports, is also in line with an executive order issued by US President Donald Trump on transgender women in sports.

IOC: 'Every Athlete Must be Treated with Dignity and Respect'

The IOC said its own research showed that athletes born as males retain advantages in strength, power and endurance due to three significant testosterone peaks: "In utero, in mini-puberty of infancy and beginning in adolescent puberty through adulthood."

It said that the male advantage ranged from 10-12% in endurance and speed-related sports like running or swimming to more than 100% in strength-based events involving lifting or punching.

"At the Olympic Games, even the smallest margins can be the difference between ‌victory and defeat," said IOC President Kirsty Coventry. "So, it is absolutely clear that it would not be fair for ‌biological ​males to compete in the female category. In addition, in some sports it would simply not be safe."

Coventry said the new regulations would ensure that "every athlete be treated with dignity and respect" and added: "There must be clear education around the process and counselling available, alongside expert medical advice."