Organizers said Williams informed them she will miss next week's Open GDF Suez tournament in Paris.
Williams also said she will sit out the United States' Fed Cup series in Italy. The Fed Cup 2013 series begins Feb. 9.
Williams, ranked No. 26 in the world, was beaten in the third round of the Australian Open by No. 2-ranked Maria Sharapova.
Her play in recent years has been limited by a series of health issues, including Sjogren's syndrome, an autoimmune disease.
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