SAN FRANCISCO — Several studies have shown that women who develop urinary incontinence during pregnancy are more likely to have postpartum and long-term incontinence. A separate randomized, controlled study suggests that cesarean delivery may protect against development of postpartum urinary incontinence.
Does that mean that women with incontinence during pregnancy should be delivered by C-section to keep the incontinence from getting worse?
No, said Dr. Sharon K. Knight at a meeting on antepartum and intrapartum management sponsored by the University of California, San Francisco. In general, 3 months after delivery the prevalence of postpartum incontinence is 9%–31%, and the incidence is 7%–15%, data suggest.
Studies show that about half of women develop transient urinary incontinence during pregnancy, which increases the risk for postpartum incontinence. The same studies report that the mode of delivery did not affect the risk of incontinence, said Dr. Knight of the university.
The one randomized study that suggested cesarean delivery might decrease the risk of postpartum incontinence had methodological problems and found a short-term benefit only in women who had no previous incontinence, she added.
That study randomized women to a trial of labor or cesarean delivery for breech babies, and the incontinence rate was a secondary outcome measure. Three months after delivery, the vaginal delivery group had nearly twice the rate of incontinence as the C-section group, but that difference had disappeared by the 2-year follow-up (Am. J. Obstet. Gynecol. 2004;191:917–27). Many of these women went on to have more babies after the study, which complicates the 2-year results because it's unknown whether they were delivered vaginally or by cesarean section, Dr. Knight noted.
Retrospective studies of women who delivered exclusively by one mode or the other have produced conflicting results on incontinence rates, but the largest population-based studies found no difference based on mode of delivery, she said.
Epidemiologic studies report that primiparous women have twice the rate of stress incontinence as nulliparous women.
By ages 50–65 years, “just being a woman puts you at high risk of having urinary incontinence,” Dr. Knight said.