The NCAA changed its participation policy for transgender athletes on Thursday, limiting competition in women’s sports to athletes assigned female at birth only.

Of the more than 500,000 NCAA student athletes, fewer than 10 of them are trans, according to NCAA President Charlie Baker.

Announced on Thursday, the National Collegiate Athletic Association said its policy applied to all athletes and was effective immediately. The policy change came the day after President Donald Trump signed an executive order preventing transgender women from competing in female categories of sports.