Not Your Mother's Delivery Room

Increased cesareans and inductions delivery times

(RxWiki News) At last, a response to elders who complain about walking barefoot in the snow uphill both ways to school: women giving birth today suffer through longer labors than women of yesteryear.

A new study that compares women's birthing experiences in the 1960s with those of the past decade has found a range of differences, including longer labor times, older mothers, and more use of certain interventions and painkillers in delivery rooms.

Researchers found that first-time mothers today are spending an average of 2.6 hours more in the first stage of labor - when the cervix is dilating before a woman begins to push - than women did in the 1960s. 

"Attend all of your prenatal appointments."

S. Katherine Laughon, MD, of the Epidemiology Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), led the study comparing the characteristics and experiences of women giving birth today compared to women 50 years ago.

Laughon's team gathered data from 39,491 deliveries between 1959 and 1966 and then compared it to data from 98,359 deliveries between 2002 and 2008, accessed from the Consortium on Safe Labor, funded by NICHD.

Even mothers who have already had one child experience an extra two hours in labor, compared to 1960s moms.

Average characteristics of pregnant women themselves have also changed over the past two generations. Women today are about eight percent heavier and four years older than women giving birth in the 60s.

The average body mass index, which measures body fat as a ratio of a person's height to their weight, of women in the 60s before getting pregnant was 23, and today the average is 24.9, barely under the threshold for being overweight, at 25.

"Older mothers tend to take longer to give birth than do younger mothers," Laughon said. "But when we take maternal age into account, it doesn't completely explain the difference in labor times."

The longer labor time may be partly explained, the authors said, from changes in delivery practices used in the hospitals, including the much higher use of epidural pain relief among today's birthing women.

While only 4 percent of women received epidurals in the 1960s, over half of today's women get an epidural, in which a painkiller is administered through an IV to a woman's spine to decrease the intensity of labor pain.

Doctors already knew that epidurals could increase the amount of time a woman spends in labor, but even the wider use of epidurals only explains part of the increase in labor time today, according to Laughon.

And the more common use of a difference intervention - giving a woman a synthetic version of the hormone oxytocin to induce labor - should have the opposite effect on labors, speeding them up.

"Without it, labor might even be longer in current obstetrics than what we found," Laughon said.

Only 12 percent of women in the 60s were given oxytocin, compared to 31 percent today. Further, in line with other studies that have found an increase in the rate of cesarean deliveries, Laughon's team found that 12 percent of today's women get cesareans compared to just 3 percent half a century ago.

Other practices, however, have become less common since the 60s, including the use of forceps to pull the baby from the birth canal and a procedure called an episiotomy, in which doctors make a small cut in the skin between the vagina and the anus to help enlarge the vaginal opening for delivery.

The differences found in the study aren't just in the mothers' labor experiences. Today's babies are arriving an average of five days earlier - and a little heavier - than their counterparts born in the 60s.

Laughon said the findings lend support to re-evaluating today's obstetric practices to see which delivery procedures are best for women and their babies.

The study was published online March 10 in the American Journal of Obstetrics and Gynecology. The research was supported by the National Institutes of Health and the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors declared they have no conflicts of interest.

Review Date: 
April 2, 2012