By Elise Viebeck - 05/29/14 05:37 PM EDT
The birth rate among U.S. teens and women in their early 20s dropped to historic lows in 2013, according to preliminary data released by the Centers for Disease Control and Prevention (CDC).
The decline was especially pronounced among women ages 15 to 19, who saw a 10 percent drop in births in one year. Their rate of birth was 26.6 per 1,000 last year.
Girls ages 10 to 14 and in their 20s also saw record-low birth rates, the agency said, calling the decreases "astounding."
The trends contributed to a record low general fertility rate of 62.9 births per 1,000 women, with roughly 4 million babies delivered in the United States in 2013.
A rise in births among older women helped stave off a further decline in the overall rate. Women ages 35 to 39 and 40 to 44 saw the highest birth rates since the 1960s.
Planned Parenthood touted the numbers as a triumph for birth control and effective sex education.
"A 10 percent drop in teen birth rates in one year is frankly astonishing," said Planned Parenthood Vice President of Education Leslie Kantor in a statement. "When young people have accurate information and resources, they make healthy decisions."
The data was released by the CDC's National Center for Health Statistics.