WASHINGTON — More women will be giving birth by caesarean section for the foreseeable future, government scientists said yesterday, releasing a study into the causes of a trend that troubles maternal health experts.
Overall, caesarean deliveries account for about a third of births in the United States. Although much attention has recently focused on women having repeat caesarean sections, researchers with the National Institutes of Health found that nearly one-third of first-time mothers delivered that way.
That is “somewhat surprising,’’ said Dr. Jun Zhang, lead author of a study that looked at nearly 230,000 deliveries in 19 hospitals around the country. “It has consequences for future pregnancies.’’ The study was published in the American Journal of Obstetrics & Gynecology.
Many doctors and hospitals follow a policy of “once a caesarean, always a caesarean.’’
The study also suggested a link between chemically induced labor and higher likelihood of a caesarean section. Women whose labor was induced were twice as likely to have a caesarean. The authors said more research is needed to clarify whether there’s a cause-and-effect relationship.
Many medical experts consider caesarean deliveries to be a major component of “overtreatment’’ in the United States.
But the trend does not appear likely to reverse. Since the mid-1990s, the caesarean section rate in the United States has risen by more than 50 percent.
The study found a variety of reasons, including heavier mothers and babies, women giving birth later in life, an increase in multiple births, and evidence that doctors may be opting for a caesarean if women have difficulties in labor’s early stages.