The mediating effect of the prolonged second stage of labor on delivery mode and urinary incontinence among postpartum women: evidence from Shandong, China

Introduction and hypothesis This study was aimed at exploring the mediating role of the prolonged second stage of labor (PSSL) in the association between delivery mode and urinary incontinence (UI) among postpartum women in Shandong, China. Methods A cross-sectional study involving postnatal women from the Women's Pelvic Floor Functional Health Center in Shandong, China, was conducted. An electronic questionnaire was used to collect the data between June 2020 and February 2021. UI was assessed using the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF). Logistic regression and multiple linear regression were employed to explore the association among delivery mode, PSSL, and UI, and the mediating role of PSSL. Results Among the total of 5,586 postpartum women included in this study, the prevalence of UI was 13.3%. Among the 742 patients with UI, the prevalence of stress urinary incontinence (78.3%) was greater than urge urinary incontinence (8.6%), mixed urinary incontinence (9.3%), and others (3.8%). After adjusting for controlling variables, delivery mode was found to be significantly associated with PSSL, whereby women with vaginal delivery were more likely to be in PSSL, and women with PSSL had a higher probability of suffering from UI. PSSL played a partial mediating effect in delivery mode and UI. Conclusions This study provided evidence that the effect of delivery mode on UI was partially mediated by PSSL among postpartum women in Shandong, China. Strategies to prevent PSSL should be actively adopted to reduce the risk of UI in women.