Birth dilemma: doctors weigh pros and cons of cesareans

Science News, Dec 18, 2004 by N. Seppa

Doctors traditionally counseled women who had had a cesarean section against delivering vaginally, even though a mother's recovery time is longer after a cesarean birth. In 1981, only 3 percent of women in the United States who had delivered by cesarean later attempted a vaginal birth. That number jumped to 28 percent by 1996, after doctors suggested that these women give vaginal birth a try under careful monitoring. But studies hinted at increased complications from labor and vaginal birth in these women, and the number fell back to 13 percent by 2002.

A new study of women with a previous cesarean finds that those attempting a vaginal delivery do indeed face a risk of uterine rupture during labor, whereas the chance of that happening in a planned cesarean is practically nil. Uterine rupture is extremely rare in women delivering vaginally who haven't had a cesarean.

Researchers monitored 17,898 women who attempted vaginal births after a cesarean and 15,801 women who stuck with cesareans and so didn't go into labor. The scientists report that 124 women attempting vaginal birth experienced uterine rupture, which typically occurs along scars from incisions made during previous cesareans. None of the women with planned cesareans had ruptures.

Of the babies born to women who attempted vaginal deliveries, 12 were diagnosed with brain injury resulting from a lack of oxygen. The problem resulted from uterine rupture in seven of these mothers and from other complications in the other five. None of the babies delivered via planned cesareans had brain injury, the researchers report in the Dec. 16 New England Journal of Medicine.

While a cesarean section carries some surgical risk, this study found about the same, low incidence of death among mothers in the two groups. In fact, the vaginal-delivery attempts resulted in more inflammation of the uterine lining than cesarean births did, says study coauthor Mark B. Landon of Ohio State University in Columbus.

He acknowledges that the overall risk of problems "is fairly small, [and] many women will continue to opt for vaginal birth after cesarean." However, he notes, "many rural hospitals are not offering this service."

In 1999, the American College of Obstetricians and Gynecologists recommended that hospitals providing women the option of vaginal birth after a previous cesarean be prepared to rush such a woman to cesarean surgery if problems arise during labor. Small hospitals often don't have the personnel on hand for that emergency surgery, says Jeanne-Marie Guise of the Oregon Health and Science University in Portland.

Meanwhile, the majority of the women in the new study who delivered vaginally did so without incident, notes Mona Lydon-Rochelle of the University of Washington in Seattle. This suggests that some women "can still be counseled to have vaginal labor after a cesarean," she says.