While everything else in the modern world is go-go-go, the miracle of birth is actually taking a little longer these days.
An analysis of nearly 138,000 deliveries has found that women in the 2000s averaged 2.6 hours longer to deliver their first child than women in the 1960s, according to a massive new study conducted by researchers at the National Institutes of Health.
A similar outcome was seen for second births, too: Modern mothers, on average, spent two more hours in the delivery room than did their mothers in the 1960s.
The finding matters because medical professionals rely on “normal” labor durations to decide when it’s time to intervene and speed up a delivery.
But the definitions about what’s normal or abnormal for labor are “based on a population of 50 years ago,” said Dr. S. Katherine Laughon, lead author of the study, which is published online in the American Journal of Obstetrics and Gynecology.
“Maybe we need to revisit these definitions,” she said.
A major concern is the increase in Caesarean surgical deliveries, which are riskier for mothers and babies than natural delivery. The new study shows that in the 1960s, 3 percent of first-time deliveries of single babies were Caesarean section, compared with 12 percent of such deliveries in the 2000s.
For years, medical professionals have used guidelines about labor duration “to draw the line in the course of a labor as to when it’s time to intervene with a Caesarean,” said study co-author Dr. D. Ware Branch of Intermountain Healthcare and University of Utah.
Now that there’s evidence that normal labor is actually taking longer than realized, “that certainly calls for a reassessment of when one should draw the line for Caesarean delivery,” Dr. Branch said.
The rise of C-section deliveries in the U.S. is a great concern because of the risks to the woman and the baby, said Maureen Corry, executive director of Childbirth Connection, which has advocated for maternal education and well-being since 1918.
Caesarean section deliveries are associated with blood clots and complications in future births in mothers, and breathing complications and other problems in newborns.
“Are providers rushing into the interventions when there’s no need?” asked Ms. Corry.
Even if the labor is taking longer, “if the mother’s OK and the baby’s OK, there’s no reason to rush into unnecessary interventions,” she said. Having a baby “takes a lot of patience and support.”
Childbirth is the most common reason for hospitalization in the United States, and federal data show that delivery procedures have changed even in the past decade.
The number of vaginal births fell from 79 percent of the total in 1997 to 67 percent in 2008, which means that 1 in 3 births overall is now delivered by use of Caesarean section, said the Agency for Healthcare Research and Quality (AHRQ) at the Department of Health and Human Services.
Caesarean delivery is typically more expensive because of longer hospital stays. The average cost of an uncomplicated vaginal delivery is $3,400, while an uncomplicated C-section costs about $5,700, according to AHRQ.
For their study, Dr. Laughon, Dr. Branch and their colleagues compared data from the Collaborative Perinatal Project, which tracked 39,491 births from 1959 to 1966, with data from the Consortium on Safe Labor, which contained information on 98,359 births from 2002 to 2008.
In addition to finding that modern mothers-to-be took two hours or more to move through their first stages of labor, the researchers found that modern mothers were older (26.8 years vs. 24.1 years) and heavier (prepregnancy body mass index was 24.6 vs. 22.6; delivery BMI was 29.9 vs. 26.3). Older age and heavier weight are associated with longer labors.
More important, there were dramatic changes in “practice patterns” in delivery rooms, the researchers said.
In the 1960s, for instance, 40 percent of births involved forceps to help pull the babies out. Forceps may have speeded up some deliveries, but the practice is unpopular now - only 2 percent of the modern births involve forceps, the NIH researchers found.
Also, performing an episiotomy - the vaginal opening is cut to ease delivery - is less common. While 68 percent of women in the 1960s had an episiotomy, only 17 percent of modern women did.
In contrast, modern women are far more likely than 1960s women to have injections of drugs during labor, which makes delivery less painful but prolongs it.