According to the National Institutes of Health (NIH), the cesarean delivery rate in the United States steadily increased from 1996 to 2004, peaking in 2004 at 29% of all live births-the highest rate on record. But does maternal preference for a cesarean delivery account for some of that increase? And does a "cesarean delivery performed at maternal request" (CDMR) improve or worsen maternal and infant outcomes?
The National Institute of Child Health and Human Development, part of the NIH, held a state of the science conference from March 27 through March 29 to examine the available evidence on CDMR. Prior to the conference, a panel of experts commissioned by the Agency for Healthcare Research and Quality prepared a report evaluating the evidence.
In addition to maternal preference, there are numerous reasons for performing a cesarean section, including medical emergencies, such as placenta previa, and risk factors that can complicate vaginal deliveries, such as obesity or advanced maternal age.
According to the evidence report, virtually no studies exist on CDMR, and the expert panel found that there have been no direct comparisons of outcomes of CDMR with vaginal delivery. Only 54 studies of even moderate relevance to CDMR were found. None had a strong level of evidence on which to base clinical decisions.
A moderate level of evidence was found to support the following conclusions: that CDMR lessens the risk of maternal hemorrhage, prolongs the length of maternal hospital stay, increases the neonate's risk of life-threatening respiratory distress, and increases the risk of placental abnormalities in subsequent pregnancies.
There was weak or no evidence to support any other conclusions. The panel concluded that "there is insufficient evidence to evaluate fully the benefits and risks of CDMR as compared to PVD [planned vaginal delivery], and more research is needed." When pregnant women request cesarean delivery but there is no medical reason to perform one, the report recommends that each case be considered individually. The provider should address the mother's specific concerns and the evidence that does exist. It further recommended that providers who prefer not to perform cesarean sections without medical indications refer women who request them to another provider.
Deanne Williams, executive director of the American College of Nurse-Midwives, expressed concern that the panel did not give more weight to the lack of evidence that CDMR is safe. She reported that many experts at the conference expressed concern that if the panel didn't say outright not to perform elective cesarean sections, its position might be interpreted by some pregnant women and their providers as "it's okay to do it." At least one expert, who testified about the direct and indirect societal costs, expressed concern that the longer maternal hospital stays and neonatal intensive care admissions associated with CMDRs are forcing some tertiary care centers to turn away the high-risk cases for which they were designed.
The panel's report cautions that "CDMR should not be performed prior to 39 weeks or without verification of fetal lung maturity," or in women who want several children, and urged that effective pain management be made available to all women regardless of mode of delivery. The report, including an audio transcript from the conference, is available at http://consensus.nih.gov/2006/2006CesareanSOS027html.htm.