The governing body of World Swimming has banned transgender women from competing in women's events since Monday.

FINA members adopted a "gender inclusion" policy on Sunday. 

This allows swimmers who have not transitioned from the pool before 12 years old to compete in women’s events. FINA also suggested an "open competition" category.

This is not to say that people should be encouraged to make the transition before they turn 12.

It’s what the scientists are saying, that if you transition after the start of puberty, you have an advantage, which is unfair,” James Pearce, who is the spokesperson for FINA president Husain Al-Musallam, told

Pearce confirmed there are currently no transgender women competing in elite levels of swimming.

The ruling would, however, excludes Lia Thomas, a University of Pennsylvania swimmer, from elite competition.

According to its recommendations, the World Professional Association for Transgender Health has just reduced the minimum age for beginning gender transition hormone treatment to 14 and some surgeries to 15.

FINA's 24-page new policy also suggested a new "open-competition" category. FINA stated that it had established "a new working group" to examine the best ways to create this category.

Pearce told the AP that open competitions would likely lead to more events. However, those details still need work.