Birth rates for teenage mothers hit another historic low last year in the United States, government researchers announced on Friday.
The number of babies born to teenagers 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 (CDC).
The teen birth rate has been falling since 1991, and has been cut in half since then.
Bill Albert of the National Campaign to Prevent Teen and Unplanned Pregnancy called the drop a "stunning turnaround."
Experts attribute the decline to a range of factors, including less sex and more use of contraception.
Overall, the U.S. birth rate might finally be leveling off after falling four years in a row, according to the report from the centers' National Center for Health Statistics.
The number of babies born last year, a little shy of 4 million, is only a few hundred less than the number in 2011.
That suggests that lately, fewer couples have been scared away from having children because of the economy or other factors, some experts say. Among the signs of a possible turning point: The birth rate for women in their early 30s inched up for the first time since 2007.
"We may be on level course or potentially even see a rise" in birth trends in the near future, said Brady Hamilton, a statistician with the CDC.
Some are a bit more pessimistic.
"The decline has slowed down, but it's still a decline," said Carol Hogue, an expert on birth trends at Emory University in Atlanta, Ga.
Falling births is a relatively new phenomenon in this country. Births had been on the rise since the late 1990s and hit an all-time high of more than 4.3 million in 2007. The drop that followed was widely attributed to the nation's flagging economy. Experts believed that many women or couples who were out of work or had other money problems felt they could not afford to start or add to their family.
The economy officially was in a recession from December 2007 until June 2009. But well into 2011, polls showed most Americans remained gloomy, citing anemic hiring, a depressed housing market and other factors.
The new report is a first glimpse at 2012 birth certificate data from state health departments, but the numbers aren't expected to change much.
Highlights of the report include:
- The birth rate for all women of childbearing age, 63 births per 1,000 women, was essentially flat from the year before.
- Rates dropped for Hispanic women, 2 percent, and black women, 1 percent, but less than the previous year. The rate continued to stay the same for white women, rose 4 percent for Asian-Americans and Pacific Islanders, and fell slightly for American Indians and Alaska Natives.
- Rates fell again for women in their early 20s, down 3 percent from 2011. That is the lowest mark for women in that age group since 1940, when comprehensive national birth records were first compiled.
- For women in their late 20s, birth rates fell 1 percent. That age group accounts for more than a quarter of all of the nation's births. The rate rose a slight 1 percent for women in their early 30s, who have nearly as many babies as women in their late 20s.
- Rates also rose 2 percent for mothers ages 35 and older, and 1 percent for women in their early 40s. Rates in older mothers have been rising slightly in recent years, despite the overall downward trend. Experts say that is because older women generally have better jobs or financial security, and are more sensitive to the ticking away of their biological clocks.
Another report highlight: About 33 percent of births last year were delivered through Cesarean section, a rate unchanged from the previous two years.
C-sections are sometimes medically necessary. But health officials believe many are done out of convenience or unwarranted caution, and in the 1980s set a goal of keeping the national rate at 15 percent.
The C-section rate had been rising steadily since 1996, until it dropped slightly in 2010.
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