Updated

FINA, the governing body for international swimming, approved new policies for transgender swimmers which will go into effect on Monday.

The "gender inclusion policy" will only permit swimmers who transitioned before the age of 12 to compete in women’s events. FINA members voted 71.5% in favor of the new policies. 

CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COM

Lia Thomas Upenn nationals

Lia Thomas looks on after winning the Women's 500 Yard Freestyle during the 2022 NCAA Division I Women's Swimming & Diving Championship at the McAuley Aquatic Center on the campus of the Georgia Institute of Technology on March 17, 2022 in Atlanta, Georgia. (Mike Comer/NCAA Photos via Getty Images)

There was also a proposal for a new "open competition policy." The organization said it was setting up "a new working group that will spend the next six months looking at the most effective ways to set up this new category."

In the 24-page policy released Sunday, FINA spelled out how transgender men and women will be allowed to compete under the new rules.

FINA said transgender men are eligible to compete in FINA competitions and set world records in the men’s category unless:

"For the disciplines of Water Polo and High Diving, the athlete must provide to FINA an assumption of risk form signed and dated by the athlete or if the athlete is a minor, by their legal proxy" or "All athletes who are undergoing treatment involving testosterone or other anabolic substances as part of female-to-male genderaffirming hormone treatment are required to obtain a Therapeutic Use Exemption (TUE) for that treatment in accordance with the FINA Doping Control Rules."

Transgender women and athletes whose legal gender and/or gender identity is female can compete in FINA-sanctioned events if "they can establish to FINA’s comfortable satisfaction that they have not experienced any part of male puberty beyond Tanner Stage 2 or before age 12, whichever is later."

Lia Thomas 2022 NCAA Division I Women’s Swimming Championship

Lia Thomas looks on from the podium after finishing fifth in the 200 Yard Freestyle during the 2022 NCAA Division I Women's Swimming & Diving Championship at the McAuley Aquatic Center on the campus of the Georgia Institute of Technology on March 18, 2022 in Atlanta, Georgia. (Mike Comer/NCAA Photos via Getty Images)

POLL ON AMERICANS’ THOUGHTS ON TRANSGENDER ATHLETES DIVIDES TWITTER USERS: 'CONFIRMS WHAT WE ALL KNOW’

The athlete must produce evidence they have "complete androgen insensitivity and therefore could not experience male puberty" or "They are androgen sensitive but had male puberty suppressed beginning at Tanner Stage 2 or before age 12, whichever is later, and they have since continuously maintained their testosterone levels in serum (or plasma) below 2.5 nmol/L" or "An unintentional deviation from the below 2.5 nmol/L requirement may result in retrospective disqualification of results and/or a prospective period of ineligibility or "An intentional deviation from the below 2.5 nmol/L requirement may result in retrospective disqualification of results and a prospective period of ineligibility equal or commensurate in length to periods imposed under the FINA DRC for intentional anti-doping rule violations involving anabolic steroids."

Transgender athlete who does not meet the eligibility standards may compete in "any open events" the organization could develop in the future.

"We have to protect the rights of our athletes to compete, but we also have to protect competitive fairness at our events, especially the women’s category at FINA competitions," FINA president Husain Al-Musallam said in a statement.

FINA's new policies go into effect Monday.

FINA's new policies go into effect Monday. (iStock)

"FINA will always welcome every athlete. The creation of an open category will mean that everybody has the opportunity to compete at an elite level. This has not been done before, so FINA will need to lead the way. I want all athletes to feel included in being able to develop ideas during this process."

Lia Thomas’ sudden emergence in the pool during the NCAA swimming season shined the spotlight on the new rules. Thomas became the first transgender swimmer to pick up wins in the NCAA and the Ivy League Championships over the last few months. She swam for the University of Pennsylvania.

CLICK HERE TO GET THE FOX NEWS APP

Thomas told Sports Illustrated last month she would seek a spot on the national swimming team ahead of the 2024 Olympics.