The Women's Tennis Association (WTA) will require all players to undergo genetic sex testing to compete on the WTA Tour.

In the latest edition of its women's eligibility policy, which will come into effect on Tuesday, players will be required to provide a cheek swab, blood or saliva sample to test for the presence of the SRY gene, which is part of the Y chromosome and causes male characteristics to develop.

Players will be tested just once in their lifetime and only a negative result, showing no presence of the gene, will permit them to compete on the Tour.

If they test positive, players will face further medical assessment before being allowed to play.

The new policy also requires players to sign a document that states they could face disciplinary action if they refuse testing.

The WTA's previous policy, last updated in 2024, allowed transgender women to compete on the Tour if they had lowered their testosterone levels to below 2.5 nmol/L continuously for the previous two years.

There are no known transgender women currently playing on the WTA Tour.

"The WTA's women's eligibility policy is designed to promote equal athletic opportunities in women's professional tennis and maintain fair competition for all players participating in WTA tournaments," the governing body said.

"Since first being introduced in 1975, the eligibility policy has undergone periodic review in light of developments across international sport.

"Following the most recent review, which included consultation with WTA members and evolving standards across women's sport, the WTA board approved an updated WTA women's eligibility policy beginning in 2026 based on biological sex."

It added: "The WTA recognises that this is a sensitive and complex issue and is committed to treating all players with dignity and implementing the policy in a respectful and thoughtful way."

The policy change comes a year after World Athletics announced new regulations - brought into effect in September 2025 - requiring athletes wanting to compete in the female category for world ranking competitions to take a one-time gene test.

World Boxing also approved the use of the SRY test in May 2025 when it introduced mandatory sex testing for all athletes wanting to compete in the women's category.