Kim Clijsters returning to women's tennis

BRUSSELS, March 25 (UPI) -- Former World No. 1 women's tennis player Kim Clijsters is on the verge of returning to the circuit following her unexpected retirement in May 2007.

Clijsters, 25, has scheduled a Thursday news conference in Belgium. She earlier said she would play this summer for the St. Louis Aces in the Advanta World Team Tennis Pro League.

The native of Belgium married American Brian Lynch shortly after retiring and gave birth to a daughter, Jada, in February 2008.

She was the top-ranked player in women's tennis for 19 weeks, won the 2005 U.S. Open and finished with 34 career singles titles. Her surprise retirement came after ongoing back and hip injuries.

Clijsters' last singles title came at the Medibank International in January 2007 at Sydney and her career record also includes two major doubles titles.

Since fellow Belgian Justine Henin also retired in May 2008, the No. 1 ranking in women's tennis has changed hands several times.