Associations Between Childbirth and Urinary Incontinence After Midurethral Sling Surgery.

OBJECTIVE

To assess whether subsequent childbirths affect the outcomes of midurethral sling surgery with regard to stress urinary incontinence (SUI).

METHODS

In this population-based cohort study, we used the validated Swedish nationwide health care registers (the Patient Register and the Medical Birth Register) to identify women with a delivery after midurethral sling surgery (n=207, study group). From the same registers we then randomly identified a control group who had no deliveries after their midurethral sling procedure (n=521, control group). The women in the control group were matched to the women in the study group by age and year of surgery. The Urogenital Distress Inventory and the Incontinence Impact Questionnaire were sent out to the study population. Symptomatic SUI was defined as the primary outcome. Secondary outcomes included the total Urogenital Distress Inventory score, Urogenital Distress Inventory subscale scores, and Incontinence Impact Questionnaire scores.

RESULTS

A total of 728 women were eligible for the study. The response rate was 74%; 163 in the study group (64 with vaginal delivery and 95 with cesarean delivery) and 374 women in the control group were included in the analysis. The rate of SUI (primary outcome) was 36 of 163 (22%) in the study group and 63 of 374 (17%) in the control group. In a multivariate regression analysis of the primary outcome, we found no significant difference between the groups (odds ratio [OR] 1.2, 95% CI 0.7-2.0). Vaginal childbirth after midurethral sling surgery did not increase the risk of SUI compared with cesarean delivery (22% vs 22%, OR 0.6, 95% CI 0.2-1.4). There were no significant differences in Urogenital Distress Inventory and Incontinence Impact Questionnaire scores between any of the groups.

CONCLUSION

Childbirth after a midurethral sling procedure is not associated with an increased risk of patient-reported SUI, and continence status is not affected by the mode of a subsequent delivery.