These findings, presented Monday at the American Urological Association's annual meeting in Chicago, add to the continuing debate on whether preventing incontinence should be a reason to schedule a C-section.
"This is the first prospective study to show a definite, persistent difference in stress urinary incontinence 12 months after delivery," says Dr. Kristene Whitmore, director of the Pelvic Floor Institute at Graduate Hospital in Philadelphia.
"From a patient perspective, it's a very provocative idea because women don't like C-sections in general, and the whole idea is that we're saying we're doing too many," says Dr. Boris Petrikovsky, chairman of obstetrics and gynecology at Nassau University Medical Center in East Meadow, N.Y.
"Clearly, [physicians] don't want to convert obstetrical service into surgical service, but in view of this information, you sort of look at the data a little differently now," he adds. "It's still very much in the gray area. It's very hard to recommend an elective C-section to a patient who may have a successful vaginal delivery."
The authors of the study maintain that using elective C-sections to prevent this type of injury remains "controversial."
The number of C-sections performed in the United States has skyrocketed, with almost one-quarter of babies now delivered this way, the highest rate since the government started collecting data in 1989.
According to the study authors, injury to the muscle tissue and nerves of the pelvic floor during vaginal delivery is the most common cause of stress urinary incontinence, or SUI. Stress incontinence is urine leakage that occurs as a result of physical activity, including laughing or coughing. Pregnancy itself, with its hormonal and mechanical changes, might also contribute to the problem.
The researchers, based in Tel Aviv, Israel, looked at 318 Israeli women who gave birth to their first baby either through vaginal delivery, elective C-section or a C-section performed as a result of difficult labor. They were assessed for stress urinary incontinence at one year after the delivery.
The prevalence of postpartum stress urinary incontinence was 12 percent for the spontaneous vaginal delivery group, and 14 percent for those who had received C-sections after obstructed labor. The women who had had elective surgery, however, had a rate of only four percent.
This doesn't mean that all these women will always be incontinent. Very often, Petrikovsky says, urinary and fecal incontinence after delivery are temporary conditions.
"When patients come with those complaints immediately after delivery, I usually advise a six-to-eight-month wait and not do anything," he says. "In the majority of them, the problem will disappear or at least diminish very significantly. So, the patients who will really have permanent problems are really a minority -- less than five percent."
Urinary incontinence is also eminently treatable, often with simple exercises that work the pelvic floor muscles, but also with surgery.
Whitmore, on the other hand, feels that women will be more likely to choose a C-section in light of this study, if their insurance will allow it. Not only would it reduce the risk of urinary incontinence, but also fecal incontinence and pelvic organ prolapse, when the bladder, uterus or bowel drops out of place.
"Up to 30 percent of women have some sort of pelvic floor disorder after labor," Whitmore says. "This study will allow women to make their own decision as to whether they want vaginal birth or not, which is not to say that C-sections do not have complications."
Petrikovsky says, "The lesson we can take out of this and other studies is that if you anticipate a difficult, long vaginal delivery, if the mother has a narrow pelvis, it's a large baby and there's a previous history of very difficult delivery, you may consider discussing C-section with the patient. Especially if she's concerned with the possibility of disruption of the pelvic floor."
For more on urinary incontinence in women, visit the National Kidney and Urologic Diseases Information Clearinghouse. For more on C-sections, visit Childbirth.org.