According to the WTA, the new rule will come into effect on Tuesday and players can conduct the once-in-a-lifetime test for the SRY gene - which helps to determine biological sex - via a cheek swab or blood test.
It is a shift away from the previous policy, where transgender players were allowed to play on the WTA Tour if they declared their gender as female and also kept their testosterone at lower levels for the required two-year period before competing professionally.
There are no known transgender women competing at the top level in women's tennis and, according to journalist Ben Rotherberg, the "WTA is the first independent professional women's sports league or tour to mandate such genetic screening for all of its athletes".
A statement issued to Bounces read: "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.
"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 Board approved a new policy beginning in 2026 based on biological sex.
"The updated policy is intended to provide a clear eligibility standard for participation in WTA tournaments. Eligibility to participate in WTA tournaments will be confirmed through a required, one-time screening process for the SRY gene. Player screening will begin in 2026, following all appropriate confidentiality and data privacy safeguards and concurrent with a comprehensive player engagement program.
"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. Additional detail can be found in the full policy."
Renee Richards was the last known transgender woman to compete professionally as she played on the Tour from 1977 to 1981 and went on to coach the great Martina Navratilova.
But 18-time Grand Slam singles champion Navratilova has been an outspoken critic of transgender athletes competing in women's sports and she welcomed the move by the WTA as she replied to a post on X: "A step in the right direction by the WTA."