Pope in good condition after hernia operation: Vatican
"Pope Francis passed a quiet night and managed to have a lengthy rest," the Vatican said.
"He is in a generally good condition, is alert and is breathing without assistance," it said in a statement.
The Argentine pontiff was "grateful" for those sending him well wishes and asked people to pray for him, it added.
Francis underwent a three-hour operation at the Gemelli hospital in Rome Wednesday, and was reportedly cheerful when he woke up.
The pope, who had colon surgery in 2021, had been suffering from a hernia on the site of a scar from a previous surgery, doctor Sergio Alfieri told reporters Wednesday.
He was placed under general anaesthesia and the abdominal wall was repaired with a surgical mesh, Alfieri said.
All papal audiences have been cancelled until June 18 to give the pontiff time to recover.
The Vatican said the pope would stay in hospital "several days", and Alfieri, who operated on him, would not be more specific.
He said the operation usually required a stay of between five and seven days, but the pope's age and illness in March -- when he was hospitalised with a respiratory infection -- may affect his recovery time.
Italian gastrosurgeon Andrea Mazzari told AFP that "in the case of older people, full recovery can take between eight to 10 days".
Francis, who has been the leader of the world's 1.3 billion Catholics for a decade, has suffered increasing health issues over the past year and his hospital stays have sparked concern and fuelled speculation over his future as pontiff.
Francis' predecessor, Benedict XVI, who died in December, stepped down in 2013 due to failing health.
Papal suite
The Argentine was admitted Wednesday after holding his weekly general audience in St Peter's Square and doing a round in his popemobile, cheerfully waving to the crowds.
He is staying in the papal suite at the Gemelli hospital, which is the favoured choice of pontiffs to the point of being dubbed "Vatican III" by John Paul II.
The suite is painted white and furnished simply. In addition to the pope's room, there is a meeting room for medical staff, a kitchen, bathroom and rest areas, as well as a small chapel.
Francis stayed there in July 2021, when he underwent surgery for a type of diverticulitis, an inflammation of small bulges or pockets that can develop in the lining of the intestine.
He was discharged after 10 days, but in an interview in January, he said the diverticulitis had returned.
Francis was also hospitalised for three nights at the end of March with a respiratory infection, which was cured with antibiotics.
For about a year, Pope Francis has had to rely on a wheelchair because of recurring knee pain.
He has said he does not want to have an operation on his knee because of the side-effects he suffered from the general anaesthesia for his colon surgery.
However, Alfieri said: "The Holy Father has never had any problem with general anaesthetic, neither two years ago nor now."
He added that the pope "does not have other illnesses".