The Risk of Stress Incontinence 5 Years After First Delivery

Abstract

To evaluate the risk of developing long-lasting stress incontinence after first delivery, the authors interviewed all women who had their first delivery at Glostrup County Hospital in 1989 (N = 305). Within a few days of delivery and again 3 months later, the women were interviewed by phone using a questionnaire that incorporated the International Continence Society standards for stress incontinence. The questionnaire included questions about urinary incontinence symptoms provoked by physical exertion, frequency of symptoms, and social or hygienic problems caused by stress incontinence. Five years later all patients were mailed the same questionnaire with additional questions about obstetric history and treatment for stress incontinence. Two hundred seventy-eight of the initial population of 305 women (91%) returned the follow-up questionnaire and form the basis of the analysis. For comparison, the women were divided into three groups. The 166 women who had no initial stress incontinence before, during, or 3 months after the first pregnancy were assigned to group 0. Eighty women experienced onset of stress incontinence symptoms with the first pregnancy; they form group 1. Group 2 includes 19 women who reported stress incontinence symptoms persisting 3 months after first delivery. Multivariate logistic regression analysis of possible contributing factors, including length of second stage of delivery, episiotomy, use of vacuum extraction, and fetal weight, was performed for all groups. One hundred seventy-two of the 278 women had a second delivery during the 5-year interval. Eighteen of these were delivered by cesarean delivery. Vacuum extraction was necessary in seven women delivering vaginally. Five women had a sphincter rupture at second delivery; 1 woman had a spontaneous rupture with no episiotomy, and 4 women in the group of 25 who had mediolateral episiotomy also sustained a sphincter rupture. Minor perineal lesions requiring sutures occurred in 75 women. There was only one perineal lesion among eight women who had a third delivery during the 5-year follow-up. At the 5-year point, 83 women (30%) had stress incontinence. Seventeen (6%) reported daily symptoms, and 23 (8%) reported social or hygienic problems due to stress incontinence. The likelihood of developing stress incontinence in the 5 years after first delivery was 3.8 times greater for women in group 1 than for women in group 0. After multivariate logistic regression analysis, only episiotomy at first delivery had borderline significance in predicting the development of stress incontinence. Compared with group 0, the risk of developing stress incontinence was 4.5 times greater for women in group 2. The use of vacuum extraction during the first delivery was the only significant risk factor remaining after analysis. Nineteen percent of the women in group 0 developed stress incontinence in the 5-year study period. No significant predicting factors were found in multivariate analysis. Among all 278 women, retrospective bivariate analysis found that episiotomy at first delivery was the only significant predicting factor for the presence of stress incontinence at 5 years. The women in group 1 had a 42% chance of stress incontinence symptoms recurring by the 5-year follow-up. In comparison, 92% of the women in group 2, those with persistent symptoms, had stress incontinence at 5 years.