"At the moment I am not capable of reaching the level that I expect of myself, and I apologize to the public and my sponsors," Hingis said.
The news comes a day after Elena Dementieva eliminated Hingis in the second round of the Porsche Grand Prix at Filderstadt, Germany.
With the loss, the world's former No. 1 will drop out of the WTA Tour's top 10 for the first time since the week of Sept. 30, 1996.
The 22-year-old Hingis, a five-time Grand Slam tournament champion, has not captured a "major" event since the 1999 Australian Open.
Earlier on Friday, Hingis pulled out of the Swisscom Challenge, a tournament that kicks off in her hometown of Zurich, Switzerland on Monday. Hingis won the event in 2000
Hingis blames her poor recent form on rushing back to action too quickly after undergoing an operation on her ankle in May.
"In order to catch up, I had to train up to five hours a day. So I neglected the therapy I needed after the operation," she said.
Aside from the Zurich tournament, Hingis will also miss events in Linz, Austria, and Los Angeles.
Hingis would not confirm whether or not she would play at the Australian Open in January.
with files from CP Online
