Research Links Pregnant Teenager's Age to Risk
A pregnant teenager's age, apart from other social or demographic factors, puts her at greater risk than an older woman of having a premature or low-birthweight baby, new research suggests.
The results of a University of Utah study of first-time pregnancies among white women in Utah challenge the notion that teenagers who receive adequate prenatal care will have as good or better chances of giving birth to a healthy baby as older women.
The finding that age is an independent risk factor for pregnant teenagers runs counter to the findings of some other studies, especially those on minority women in inner cities.
Socioeconomic factors such as insufficient education and inadequate prenatal care have been thought to make more of a difference on the outcome of a pregnancy than the mother's age.
While the Utah study found prenatal care, for example, to improve the chances of a successful pregnancy, the researchers also found that when they looked at the most privileged girls, the youngest mothers still had the highest risks.
The study, which looked at records for 134,088 white girls and women between the ages of 13 and 24 who gave birth between 1970 and 1990, was published in the April 27 New England Journal of Medicine.
The researchers found that even among the women who were educated at a level appropriate to their age and had adequate prenatal care, a teenager younger than 18 still had a higher risk of having a premature or low-birthweight baby or one that was small for its gestational age.
The risk that was most elevated for the under-18 age group was for delivering a premature infant. These girls had twice the risk of mothers who were 20 to 24 years old, according to Ryk H. Ward, an author of the study and an associate professor of human genetics.
Mr. Ward and his colleagues also found that among the under-18 group, the younger the teenager, the greater the risks to her infant.
For the youngest mothers studied--those 13 to 15--who had the various social and economic advantages offered by marriage, age-appropriate education, and adequate prenatal care, the risk of a low-birthweight or premature infant was still higher than for the 16- and 17-year-olds.
The mother's age could be a risk factor, the authors write, because a girl's reproductive organs may not yet be fully mature and because she may still be growing and competing for nutrients with a developing fetus.
Because the risks of adverse outcomes increased as the woman's age decreased, the biological factor is a strong one that would apply across racial and ethnic groups, Mr. Ward said.
Advice for Programs
In an editorial in the same issue of the journal, researchers at the University of Alabama at Birmingham note that other research suggests little intrinsic risk of problem births for girls at the beginning of their reproductive years, especially if they have been menstruating for at least two years.
But Mr. Ward said that biological changes continue until age 18 or 20 that could explain the problems in births among young women.
Programs aimed at curbing teenage pregnancy need to focus on the message that "it is not good for either the mother or the baby to get pregnant at an early age," Mr. Ward said.
And that message needs to go out more forcefully to white, middle-class girls, he said.
If a teenager is pregnant, Mr. Ward said, it is important that she have access to prenatal care.
Both he and the Alabama researchers who wrote the journal's editorial criticized proposals that have been floated in Washington to curb welfare payments to pregnant and parenting teenagers.