The Medical Minute: Caesarean delivery -- a choice or a necessity?

By John Messmer
Penn State Family and Community Medicine
Penn State Milton S. Hershey Medical Center
Penn State College of Medicine

Mary is a 38-year-old professional, pregnant with her first child. She is compulsive about her schedule and planned her pregnancy so the baby would be born well before an important conference later in the year. She read an article about urinary incontinence in women from the stretching of the support muscles of the bladder due to labor and wants to avoid that if she can. She decided to request a planned Caesarean section one week before her baby is due.

Almost a third of babies in the United States are now delivered by Caesarean section -- a 40 percent increase since 1996. Some of those are for women who had a previous Caesarean delivery since a previous Caesarean makes it more likely subsequent babies will be Caesarean deliveries. However, one in five births is by a first time C-section.

Part of the increase comes from women requesting a Caesarean delivery. The Caesarean delivery on maternal request or CDMR is interesting because a generation ago, there was a movement for vaginal birth after Caesarean section (VBAC) as a way to restore the natural process of childbirth. Many people believed that if a prior baby was delivered by C-section due to fetal distress rather than because there was insufficient room in the birth canal, it was possible to give the woman a chance to deliver vaginally. The number of vaginal birth after Caesarean sections peaked in 1996 and have been dropping since, although only part of this reduction is explained by Caesarean delivery on maternal request.

It is not completely clear why women are requesting Caesarean delivery before trying a course of labor, but suspected reasons include convenience of knowing when the delivery will be and suspected reduction in risk of later bladder control problems. This is not an American phenomenon; women in other countries are part of the trend. Seeking to understand it, the National Institutes of Health (NIH) have studied the issue, recently releasing a statement on women requesting Caesarean deliveries.

Many news outlets reported that the NIH found Caesarian deliveries as safe as vaginal delivery. The truth is slightly different. The NIH actually said there was not enough evidence to make a case for or against the practice. That is, no one actually knows, as it has not been studied.

CDMR in this case refers only to a mother's request to have her baby delivered by C-section when there is no medical reason for doing so. There are a few potential benefits of a planned C-section. Hemorrhage after delivery is less in planned Caesarean delivery. Urinary incontinence is less likely if no labor has taken place. However, the NIH could not determine how long the benefit will last and whether it is negated by being overweight or by advancing age.

Trauma to the vagina and surrounding structures is less with planned C-section. Maternal infection is less with vaginal delivery as are anesthesia complications. Possible advantages to the baby include lower mortality rate and less brain hemorrhage, less birth injury and less infection, but the evidence for these benefits is very weak.

Countering the potential benefits there is evidence for greater harm from C-section. Subsequent pregnancies after C-section are more likely to have the placenta over the lower uterus, called "placenta praevia," which can result in hemorrhage and fetal death. After Caesarean delivery, women are less likely to breast feed and uterine rupture is more likely in future deliveries after C-section -- a particular problem for women who desire large families. Babies born by C-section are more likely to have respiratory distress and mother and baby stay longer in the hospital after C-section.

No evidence has been found to determine whether anal continence or sexual function is affected or whether uterine or bladder support is damaged more by C-section or by vaginal delivery. The problem with all these findings is the data is weak. Too few maternally requested C-sections have been studied to make any definite recommendations.

Until good data are available, it is difficult to make general recommendations about a decision to plan an elective Caesarean delivery when no medical reason exists. The NIH recommends assurance of maturity of the baby's lungs before elective delivery. The C-section should not be motivated by a desire to avoid the pain of childbirth since effective pain management is available. Postoperative pain from a C-section lasts longer in most cases than labor pain. The decision must be made individually in consideration of the woman's future pregnancy plans, her overall health, the course of the pregnancy and her reasons for wanting a planned C-section until further study has been done.

To read the NIH consensus report on Caesarean delivery on maternal request, go to http://consensus.nih.gov/2006/2006CesareanSOS027html.htm online.