ATLANTA -- American women, encouraged by a decade-long economic boom, are having more children than at any other time in the past three decades -- 2.1 on average in a lifetime, the government said Tuesday.
For the first time since 1971, women are producing enough children to offset deaths in the United States, the National Center for Health Statistics said.
The center reported 4,058,814 births in 2000, the latest year for which figures were available -- up 2.5 percent from 1999. It was the first time since 1993 that births topped 4 million.
Researchers said the roaring economy of the 1990s was probably a major factor, helping potential parents feel more comfortable about supporting a family.
"Their financial security was increasing, and they could afford additional children. And then we had this continuing increase in postponed childbearing," NCHS demographer Stephanie Ventura said.
The national birth total breaks down to an average of 2.13 children for every woman through her childbearing years of 15 to 49. The government uses 2.1 as the figure necessary for a population to fully replace itself.
Teen birth rate declines
The report showed increases in the birth rate in 2000 among women of all age groups except teen-agers. Births to 15- to 19-year-olds dropped to 48.5 for every 1,000 women, an all-time low. The teen birthrate was 49.6 in 1999.
"The credit goes to the teens themselves," said Sarah Brown, director of the National Campaign to Prevent Teen Pregnancy. "There are only two ways these rates can go down -- less sex and more contraception. There's evidence that these teens are doing both."
Researchers believe the strong economy, coupled with a strong fear of sexually transmitted diseases, probably played a role in cutting teen births, which dropped 22 percent in the decade.
"They could see they should be spending time improving their education and occupational skills, and postponing marriage and childbearing," Ventura said.
The report also found that smoking among pregnant women declined for most age groups, down to 12.2 percent in 2000. That rate has fallen steadily since 1989. The report found 12 percent of babies born to smokers had low birthweight, compared with just 7 percent of babies born to nonsmokers.
The rate of twins rose slightly, extending a two-decade-long trend.
"Older moms are more likely to have multiple births," said Joyce Martin, a NCHS epidemiologist. "And you have the added whammy of fertility-enhancing therapy, both the drugs and the techniques."
But sets of triplets and higher-order births are on the decline, the report found. Health officials hope that decline means women might be heeding their warnings about fertility procedures, which often produce multiple births that put the children at risk.