Lindsay Davenport won three out of four tennis matches after she made her return only three months after having a son she has called Jagger.
But Davenport was beaten in the second round of the Australian Open in February by Russian star Maria Sharapova and in April she was forced to pull out from the semi-finals of Amelia Island Championships in Florida because of sickness.
In the past Lindsay Davenport won an Olympic gold with the USA in 1996 and she was victorious at the US Open in 1998.
Davenport's fellow-American tennis players Meilen Tu and Meghann Shaughnessy have also withdrawn due to injuries.
