The 50-year-old TV personality also said Monday on her blog that she is selling original paintings on eBay to raise money for the Desmoid Tumor Research Foundation.
A spokeswoman for O'Donnell confirmed the nuptials and fundraising efforts.
Rounds was diagnosed with desmoid tumors in June. She and O'Donnell wed in New York on June 9, and Rounds underwent surgery June 14. Desmoid tumors occur rarely and can affect almost any area of the body. The tumors can be fatal.
O'Donnell has had health issues of her own. She said Aug. 20 that she recently suffered a heart attack.