Vaginal birth does not contribute to the development of stress urinary incontinence later in life, according to Dr. Gunhilde Buchsbaum, of the department of ob.gyn at the University of Rochester (N.Y.), and colleagues.
“Contrary to the conventional wisdom that nulliparity protects against stress urinary incontinence, we found similar rates of urinary incontinence in postmenopausal nulliparous women and their parous biological sisters,” the investigators reported (Obstet. Gynecol. 2005;106:1253–8).
Dr. Buchsbaum's team analyzed a sample of 143 pairs of nulliparous/parous postmenopausal sisters. All of the women answered a questionnaire about symptoms of pelvic floor disorders, and 101 pairs also underwent clinical evaluation of urinary incontinence and genital prolapse. The researchers found that 47.6% of nulliparous women and 49.7% of parous women reported urinary incontinence, with no difference in type and severity of urinary incontinence between the groups.
Of interest was the finding that there was “a high concordance in continence status … within biological sisters,” according to Dr. Buchsbaum. This finding suggests that there may be a genetic predisposition for urinary incontinence. If that proves to be true, it “would have great implications for the direction of basic research, treatment approaches, risk management, and potential prophylactic interventions.”