With Serena Williams’ announcement that she is expecting her first child this fall and new mom Victoria Azarenka returning to action later this summer, here’s how the WTA’s Special Ranking Rule applies to both players and in all maternity cases:

To be eligible, a player must be out for a minimum of six months, maximum of two years and be ranked inside the Top 300 (or Top 200 in doubles) at time she stopped playing. The Special Ranking application and supporting medical documentation must be submitted within six months after the last professional tournament played.

For maternity cases, players must be ready to play their first tournament within 12 months of birth.

The Special Ranking will be the ranking earned immediately after the points of the last tournament she played have been added to the WTA Rankings:
-For Serena Williams, her Special Ranking would be No.1
-For Victoria Azarenka, her Special Ranking is No.6

Upon return, a player may use her WTA Special Ranking to gain entry (not for seeding) into eight tournaments within one year of her return date. The Special Ranking can be used at a maximum of two Premier Mandatory Tournaments (Indian Wells, Miami, Madrid, Beijing) and two Grand Slams.

In addition, any player who is a past singles champion of a Grand Slam or WTA Finals will be allowed an unlimited number of Singles Main Draw Wild Card nominations.

The complete details can be found in the 2017 WTA Rulebook – Special Ranking Rule: pg. 218-225; Singles Main Draw Wildcards: pg.67