The surgery, performed through a small incision in the abdomen, lasted several hours and was completed by around 1:30 a.m. Wednesday. Surgeons cleansed her abdominal area with fluid and closed a nearly six-tenths of an inch hole caused by the ulcer, Reardon said.
Family spokesman Jim McGrath said Bush had had minor pain for several days but that by Tuesday she needed medical attention.
Reardon said Bush declared that "this was the worst pain she ever had, worse than childbirth," and had the Secret Service bring her to the hospital.
If not properly treated, perforated ulcers can be life threatening, he said.
Former President George H.W. Bush as well as other family members were with the former first lady during the day, McGrath said.
Reardon did not know what caused the ulcer but they can be side effects of nonsteroidal anti-inflammatory drugs, which Bush is taking. He would not say why.
Reardon said the first thing Barbara Bush did after she woke up from the surgery was tell him a joke.
Laura Bush, the current first lady and Barbara Bush's daughter-in-law, said earlier Wednesday: "She's doing great. George and I talked to both President Bush and Barbara Bush last night while they were in the hospital and they were both doing very well then."
The former Barbara Pierce, daughter of the publisher of McCall's magazine, married George H.W. Bush in January 1945 when he returned a hero from World War II.
She was the girl who, swept off her feet by a handsome Navy aviator, dropped out of college to marry him, "the first man I ever kissed."
They had had their first child, George, while still at Yale in 1946. A daughter, Robin, died in 1953 of leukemia a few weeks before her 4th birthday. The other Bush children are sons Jeb, Neil and Marvin, and daughter Dorothy.
Barbara Bush disclosed she was suffering from an overactive thyroid ailment known as Graves' disease when she lived at the White House. The disease causes teary eyes and double vision in Bush, according to her doctors.
