The birth rate among US teenagers hit another record low last year in what experts are calling a "stunning turnaround."
The number of babies born to teenagers in 2012 was about 305,000, less than half the peak of nearly 645,000 in 1970, according to the new report from the Centers for Disease Control and Prevention.
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The US teen birth rate has been falling steadily since 1991, and is now half the rate it was then.
Bill Albert of the National Campaign to Prevent Teen and Unplanned Pregnancy called the drop a "stunning turnaround" in an interview with The Associated Press.
So what's behind the big drop?
Experts rattle off a range of factors, from less sex among teens to a higher use of contraceptives.
Birth rates among US women overall have also been falling in recent years, largely due to the economy, according to the report from the centers' National Center for Health Statistics.
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However, experts point out that US teen birth rates are much higher than other industrialized countries.
And Carol Hogue, an expert on birth trends at Emory University in Atlanta, fears the decline is slowing down.
"The US has made remarkable progress, obviously," Albert told US News & World Report. "But we are an outlier, even taking into account these impressive declines. There's no doubt about it."