The number of babies born in conflict zones increased by more than 125,000 this year to 16.6 million compared with last year, the United Nations said on Wednesday.
The figure translates to 1 in 8 of all births worldwide in 2015, according to data released by UNICEF.
"Can there be a worse start in life?" said Anthony Lake, UNICEF's executive director.
Protracted civil wars have put civilians at risk in a slew of countries including Syria, the Central African Republic and South Sudan.
Last year, 16.4 million babies were born into conflict zones, rising this year to 16.6 million, UNICEF said.
One of those babies was a boy named Dilgesh, born to Syrian asylum seeker Nahide, age 19, UNICEF field worker Christopher Tidey told the Thomson Reuters Foundation in an interview.
Separated by the war from her parents, the young mother and her 7-month-old son traveled by themselves through Turkey, he said.
"I was really kind of in awe of this person, the inner strength that she has," he said.
Children born in war are apt to suffer unhealthy emotional and cognitive development and are more likely to die before age 5 than are children born elsewhere, UNICEF said.
Babies also may suffer if they were conceived as a result of rape committed in conflict, said Debra DeLaet, professor of political science at Drake University in Des Moines, Iowa, who has written on the topic.
"There are instances of some women attempting to kill children at birth," she said.
Others are vulnerable to being abandoned or rejected by family members, she said.
Next year, the U.N. agency said it projects an increase to 16.7 million babies born in conflict zones.
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