KPRC-TV in Houston reported the former first lady was "resting comfortably" at Methodist Hospital, where she was admitted Tuesday night.
The spokesman said the 83-year-old Barbara Bush had a 1-centimeter hole in her stomach, which was repaired through a small incision in her abdomen. The surgery was completed about 2 a.m. EST Wednesday, ABC News reported
Bush, accompanied by her husband, former President George H.W. Bush, was hospitalized after complaining of pain in her abdomen. Her surgeon, Dr. Pat Reardon, said Wednesday afternoon she told him the ulcer was "the worst pain she had ever felt," ABC said.
The former first lady was expected to stay in intensive care for at least 24 hours and likely would remain hospitalized until next week, the network said. She won't be able to eat for about that long and will receive antibiotics intravenously.
Reardon said Bush was doing very well, and her vital signs were stable.
Bush's daughter-in-law, current first lady Laura Bush, told ABC her mother-in-law was "doing great."
"The White House doctor did talk to Barbara Bush's doctor, and she's doing very well, and we're really, really thankful," Laura Bush said.
Notable deaths of 2014 [PHOTOS]