The changes were prompted, in part, by the experiences of former No. 1 players Serena Williams and Victoria Azarenka, both of whom returned to competition after giving birth.

The WTA announced that players returning to the tour may use a special ranking for up to three years after the birth of a child, and the exemption can be used for seedings at big events.

Williams, who owns an Open-era record 23 Grand Slam singles titles, was unseeded at this year's French Open in her first major since the birth of her daughter — despite having won the previous major she played, the 2017 Australian Open. Williams was seeded 25th at Wimbledon and 17th at the U.S. Open, and she reached the finals and lost at both of those majors.

Players who return from an injury that keeps them out of competition for a year or longer may use a special ranking in 12 tournaments. No player will be bumped from her earned seeded position.

"These changes," WTA CEO and chairman Steve Simon said, "are designed to fully support players in their return to competition, while maintaining the highest standards of athletic competition and fairness."

The tour also said it will ensure women at WTA tournaments "are not penalized or prohibited from wearing leggings or compression shorts without a skirt, dress or shorts over them."

Williams wore a black bodysuit at the French Open, where she pulled out with an injury before the fourth round. Williams said she wore the compression suit because of a history of blood clots, including after childbirth.

This fall, the president of the French Tennis Federation said Williams could no longer wear the black bodysuit at the French Open.

Azarenka, a member of the WTA Players' Council, said she wants to make sure the WTA is "the most progressive and inclusive association in sports."

"Our players should feel comfortable and confident to take time away from the courts to have a family or recover from injury," Azarenka said.