The Pennsylvania Senate has approved a Republican-backed bill banning transgender women from participating in high school or collegiate women’s sports. The “Fairness in Women’s Sports Act,” which was passed Tuesday by a vote of 30-20, requires sports teams to designate teams as male, female or co-ed.

The bill defines “sex” as “the biological distinction between male and female based on reproductive biology and genetic make-up.” It excludes gender identification as a factor for team assignment.

Senators Judy Ward Kristin Phillips-Hill issued a memorandum in support the bill. They wrote, “It’s imperative that we protect the opportunity for female athletes to compete on the athletic field in a fair and equal manner. Allowing a biological male to compete on a women’s scholastic team puts all women on the playing field at an automatic disadvantage.”

They claim that allowing transgender women to participate in women’s sports would undo the progress made since the passing of Title IX. According to the memorandum, “Maintaining separate, biologically specific teams will ensure opportunities for women athletes, while fulfilling the goals of Title IX. Title IX was designed to end discrimination and create equal athletic opportunities for women.”

The legislation now heads to the House, where identical legislation was recently approved. Beth Rementer, a spokesperson for Pennsylvania Governor Tom Wolf, has said that Wolf will veto the legislation if it makes it to his desk.

Pennsylvania is the latest in a series of states to advance similar legislation, including South Carolina, Ohio and Oklahoma, among others.