WASHINGTON Fewer U.S. teens got pregnant in 2004 but more women in their 20s had out-of-wedlock pregnancies, according to new federal statistics released on Monday.
The latest look at U.S. pregnancy trends also shows more women are keeping their babies even if they are not married, with the exception of black women.
While 45 percent of all pregnancies are among women who are not married, the typical "unwed mother" is no longer a teenager but in fact an older woman, said Stephanie Ventura of the Centers for Disease Control and Prevention's National Center for Health Statistics.
"More of them are likely to have the baby rather than having an abortion compared to 1990," Ventura, who led the study, said in a telephone interview.
The report found that nearly 38 percent of pregnancies in 2004 were to women under the age of 25, which is down from nearly 43 percent in 1990.
Just 12 percent of all pregnancies were to teenagers, compared to 15 percent in 1990.
Overall, there were almost 6.4 million pregnancies in 2004 among U.S. women of all ages, down 6 percent from 1990.
Out of these pregnancies, 4.11 million babies were born. There were 1.22 million abortions and 1.06 million stillbirths and miscarriages. That means 64 percent of all pregnancies resulted in a live birth.
In 2006, 4.3 million live babies were born but data is not yet complete on abortions.
Ventura said it takes years to gather this kind of data.
She said other studies have shed light on why pregnancy rates are going down among teens.
"There have been some changes in behavioral and contraceptive use among teenagers who are sexually active," Ventura said.
The report said pregnancy rates fell the most among sexually experienced teens, suggesting that better use of contraception may be responsible
"There is some evidence that contraceptive use (for example, at first intercourse and at most recent intercourse) was increasing among teenagers through 2002," they wrote.
Meanwhile, more women are delaying childbearing.
"Among older women, birth rates have been going up -- that's something we have been watching for 20 to 30 years," Ventura said.
According to the study, 77 percent of births to unmarried women in 2006 were to women 20 and older.
"I guess maybe it is changes in attitude and a willingness
to have children when you are not married and that kind of thing," Ventura said.
About 3.5 million pregnancies were among married women and 2.98 million were to unmarried women.
"There are large racial disparities in most of these measures," Ventura said.
About two-thirds of white and Hispanic women who got pregnant ended up having their babies while 48 percent of black women did. Thirty seven percent of pregnancies to black women were aborted.
There are two possible reasons for this, the report found.
"First, non-Hispanic black women were less likely to use a contraceptive method at first intercourse and currently than white women," the researchers wrote.
Second, blacks had double the rate of "contraceptive failure" compared to whites.
(Editing by Julie Steenhuysen and Bill Trott)