Postpartum urinary incontinence – types, prevalence, and risk factors before, during, and after pregnancy and childbirth: a prospective cohort study

Objective To assess the extent to which delivery mode and antepartal and postpartal risk factors increase the risk of postpartum stress and urge urinary incontinence. Design Prospective cohort study. Setting Women registering at the maternity health care service in Region Örebro County, Sweden. Population A total of 670 women. Methods Outcome measures were based on questionnaires in early and late pregnancy and at 8 weeks and 1 year postpartum. Generalized linear models were used. Main Outcome Measures Significant stress and urge urinary incontinence at 1 year postpartum in women who were continent before pregnancy. Results Stress and urge urinary incontinence were reported by 21% and 8%, respectively, at 1 year postpartum. Vaginal delivery increased the risk of stress (aRR=2.63 [95% CI: 1.39, 5.01]) but not urge incontinence. This effect of vaginal delivery on stress incontinence was similar irrespective of incontinence status during pregnancy. The population attributable fraction of stress incontinence associated with vaginal delivery was 0.58 (95% CI: 0.23, 0.77). Conclusions This study shows essentially different risk factors for stress and urge urinary incontinence, supporting stress incontinence as being the subtype mostly associated with pregnancy and childbirth. At population level, vaginal delivery was the major risk factor for stress incontinence, but preventive use of caesarean section for this matter is debatable. Funding ALF funding from Region Örebro County (Grant Nos. OLL-930507 and OLL-939402) and Örebro University Hospital Research Foundation (Grant No. OLL- 410421). Keywords Postpartum urinary incontinence, stress urinary incontinence, urge urinary incontinence, risk factors, prospective, cohort study