LONDON (AP) ― More than 2 million babies are stillborn every year worldwide and about half could be saved if their mothers had better medical care, according to research estimates published Thursday in the medical journal Lancet.

While the vast majority of stillbirths happen in the developing world, the rates in countries including Britain, France and the U.S. have not dropped to the degree that many experts had expected, as rising obesity levels among pregnant women increase the risk.

Experts say providing better obstetric care, treating conditions like syphilis, high blood pressure and diabetes in mothers, among other strategies, could save more than 1 million infants every year. The research was paid for by organizations including Save the Children, the World Health Organization and the Bill & Melinda Gates Foundation.

“It’s a scandal there are so many stillbirths that can be prevented,” said Joy Lawn, director of global evidence and policy at Save the Children in South Africa, who led the Lancet series. She said the politics of public health has meant the stillbirths problem has been sidelined by maternal and child health programs, even though there are more stillbirths than children killed by AIDS and malaria combined.

In developing countries, most stillbirths are caused by delivery complications, maternal infections in pregnancy, fetal growth problems and congenital abnormalities. In developed countries, the reasons are often unclear why stillbirths occur, and surveillance and autopsy data are patchy.

But the researchers’ estimates have a wide margin of error: The numbers range between 2.1 million to 3.8 million stillbirths a year. Those figures are based on reported statistics from 33 countries, largely in the West. For the other 160 countries, where the most stillbirths occur, scientists relied on modeled estimates.

William Easterly, an aid development expert at New York University, said the numbers were based on too little information to be reliable. He was not connected to the research.

“It’s basically made-up data,” he said.

Easterly said he was glad to see stillbirths on the global agenda, but warned the estimates could distort public health policy.

Finland and Singapore had the lowest stillbirth rates worldwide ― two per 1,000 births ― while Nigeria and Pakistan were at the bottom of the list, with 42 and 47 stillbirths, respectively, per 1,000 births. In the U.S., there were six per 1,000 births, though the rate is nearly double for African-American mothers.

In an accompanying commentary, Gary Darmstadt of the Bill & Melinda Gates Foundation said it wouldn’t cost much to prevent many stillbirths. “If all we did was to provide good-quality care during childbirth, at a cost of less than $1 per head, we could avert 1.4 million deaths of mothers, (babies) and stillbirths,” he wrote.

But with weak health systems in countries where most stillbirths occur, Easterly said saving lives wouldn’t be that straightforward.

“Health technologies don’t implement themselves,” he said. “The care still needs to be provided by health workers who have very complex motivations in often poor and corrupt health systems.”

Health officials announced a new target of reducing stillbirths by at least half by 2020. They estimate they will need $10 billion a year for comprehensive health packages for pregnant women and their babies.

For Samantha Baker, who had a stillborn daughter, Scarlett, any efforts to understand why stillbirths happen and how to avoid them are welcome. Baker said Scarlett’s umbilical cord twisted around her neck and suffocated her when she went into labor.

“I can’t think of a worse tragedy to happen to expecting parents,” she said. Baker, an accountant in Kent, south of London, now works with Sands, a British charity that supports families affected by stillbirths.

Baker and her husband spent several hours with Scarlett after she was born in December 2009. “The hardest thing was leaving her at the hospital,” she said. Three weeks ago, Baker gave birth to a son, Harry. She and her husband also have an older daughter, Sydney.

She hopes the Lancet series will promote more efforts to reduce stillbirths and provide support for stricken families. “Nobody ever wants to talk about (stillborns) because it’s so sad,” she said. “But not every pregnancy ends happily.”