The couple wed on June 9 at a private ceremony in New York after getting engaged in December 2011, reports People.
O'Donnell's rep shared: "They got married but they haven't had the wedding celebration."
The couple apparently planned to wed in August, but moved up the date after Rounds was diagnosed with rare desmoid tumours.
Rounds had her first surgery on June 14 and the rep said she is recovering.
She said: "It is such a rare tumor. It took them quite a while to get an accurate diagnosis. She had several gastrointestinal surgeries to remove the desmoid tumours. She is now on the road to recovery."
O'Donnell, who also announced their marriage on her blog, recently suffered a heart attack.
Watch a news clip reporting Rosie O'Donnell's heart attack below: