Daniel Grill / Getty Images

(Updated) Better birth control? No, it’s the bad economy. The national birth rate dropped for the third straight year, down another 3% in 2010, and experts say it’s because women fear they can’t afford the cost of kids.

According to a Centers for Disease Control and Prevention (CDC) report released Thursday, birth rates dropped in all racial and ethnic groups and in most age groups from 2009 to 2010. But they fell most precipitously in teens and young women: in teens aged 15 to 19, the birth rate declined 9% to 34.3 births per 1,000 females in 2010, the lowest ever reported in the U.S. In women aged 20 to 24, the birth rate fell 6% to 90 births per 1,000 women, also a record low. Births to unmarried women also dropped 4% from 2009 to 2010.

The trend lines closely mirror the economic downturn. U.S. births hit a record-high 4.3 million in 2007. After the official start of the recession in December 2007, births started dipping, and declined steadily in 2008 and 2009. By 2010, U.S. births were down to about 4 million.

“I don’t think there’s any doubt now that it was the recession. It could not be anything else,” Carl Haub, a demographer with the Population Reference Bureau who was not involved in the study, told the AP.

MORE: Teen Sex Update: Fewer Teens Doing It, More Boys Using Condoms

Other experts, however, were quick to attribute the falling birth rates to other factors, including increasing access to contraception and the success of pregnancy awareness campaigns. “The magic formula of less sex and more contraception is responsible for this great good news,” said Sarah Brown, CEO of the National Campaign to Prevent Teen and Unplanned Pregnancy, in a statement. “Teens are being more careful for a number of reasons, including the recession, more media attention to this issue — including the ‘16 and Pregnant/Teen Mom effect’ — and more attention to and investment in evidence-based programs. But at the end of the day, the thanks and admiration go to teens themselves.”

Other notable findings from the CDC report:

The total fertility rate — or, how many children women can be expected to have in their lifetime, if current birth rates continue — dropped to 1.9. Typically, the U.S. fertility rate is over 2. Among Hispanic women, the fertility rate dropped from nearly 3 children a few years ago to 2.4 children in 2010.

The birth rate for women in their early 40s increased, from 10 births per 1,000 women in 2009 to 10.2 births per 1,000 women in 2010 — the highest birth rate for this age group since 1967.

The rate of cesarean deliveries declined for the first time since 1996. It fell slightly from 32.9% of all deliveries in 2009 to 32.8% in 2010. That could be the result of reductions in medically unnecessary c-sections, but it’s too early to tell whether the trend has really reversed.

The preterm birth rate fell for the fourth straight year in 2010, to just under 12% of all births — a 6% drop from 2006.

MORE: What Teen Sex on “Glee” Really Teaches Kids

To view the full report, download a PDF here.

Correction [2:45 p.m.]: Due to an editing error, the original version of this story misstated that 1946-47 was the first year the government recorded birth rate data. In fact, the year was 1918.



Meredith Melnick is a reporter at TIME. Find her on Twitter at @MeredithCM. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.