Cumulative incidence of urinary incontinence and associated factors during pregnancy and after childbirth: a cohort study

Introduction and hypothesis This study examined the associated factors (i.e., obstetric and maternal-newborn factors) related to cumulative incidence of urinary incontinence and changes in urinary incontinence during pregnancy and the first year postpartum. Methods This prospective, longitudinal, within-subject study included 501 women who completed the Incontinence Questionnaire-Urinary Incontinence Short Form during pre-pregnancy, early pregnancy, mid-pregnancy, and late pregnancy and at five time points during the first year postpartum. Data were analyzed by multivariate logistic regression, McNemar’s and analysis of variance (ANOVA) tests. Results According to the multivariate analysis, the gestational week and number of previous vaginal deliveries increased the risk of cumulative incidence of urinary incontinence (CIUI) during pregnancy (both p < 0.05). Full-time employment, higher body mass index, vaginal delivery and UI during early pregnancy and mid-pregnancy increased the risk of CIUI during the first year postpartum (all p < 0.05). CIUI tended to increase throughout the entire pregnancy ( p < 0.001) and decrease from 3 to 5 days to 6 months postpartum ( p = 0.028). The prevalence rates of UI at all postpartum visits were lower than those during late pregnancy ( p < 0.001–0.009) but higher than those during pre-pregnancy ( p < 0.001). Conclusions The results identified the change patterns in UI and the risk factors associated with CIUI during the entire pregnancy (i.e., gestational age and number of previous vaginal deliveries) and the first year postpartum (i.e., full-time work, higher body mass index, vaginal delivery and UI during early and mid-pregnancy). Appropriate counseling should be provided to women preparing for pregnancy and during the prenatal and postpartum periods.