WASHINGTON (AP) -- A new report finds some 15 million premature babies are born every year -- more than 1 in 10 of the world's births and a bigger problem than previously estimated.

The first country-by-country count of the problem shows most preemies are born in Africa and Asia. But it's a problem for the U.S., too, where half a million babies are born too soon -- and at a rate far higher than in Europe or other similar countries.

The toll: some 1.1 million of the world's preemies die. The report estimates that three-quarters of the deaths could be prevented by spreading some simple, inexpensive treatments to low-income countries -- including teaching "kangaroo care," in which moms carry their tiny babies nestled skin-to-skin on their bare chests for warmth when there are no incubators.