Objective: To evaluate the effect of the fetal head station at attempted operative vaginal delivery (aOVD), and specifically midpelvic or low aOVD, on urinary incontinence (UI), anal incontinence (AI), and perineal pain at 6 months.
Design: Prospective cohort study.
Setting: 1941 women with singleton term fetuses in vertex presentation with midpelvic or low aOVD between 2008 and 2013 in a tertiary care university hospital.
Methods: Symptoms of urinary incontinence (UI) using the Bristol Female Lower Urinary Tract Symptoms questionnaire, and symptoms of anal incontinence (AI) severity using Fecal Incontinence Severity Index (FISI) were assessed 6 months after aOVD. We measured the association between midpelvic or low aOVD and symptoms of UI, AI, and perineal pain at 6 months using multiple regression and adjusting for demographics, and risk factors of UI and AI, with adjusted odds ratios (aORs) and 95% confidence intervals (95% CI).
Results: The study included 907 women (46.7%) who responded to the questionnaire; 18.4% (167/907) had midpelvic aOVD, and 81.6% (740/907) low; and none of women with symptoms of UI (26.6%, and 22.4%, respectively; p = 0.31), AI (15.9%, and 21.8%; p = 0.09), the FISI score, and perineal pain (17.2%, and 12.7%; p = 0.14) differed significantly between groups. The same was true for stress, urge, and mixed-type UI, severe UI and difficulty voiding. Compared with low pelvic aOVD, the aORs for symptoms of UI in midpelvic aOVD were 0.70 (0.46-1.05) and AI 1.42 (0.85-2.39). Third- and fourth-degree tears were a major risk factor of symptoms of UI (aOR 3.08, 95% CI 1.35-7.00) and AI (aOR 3.47, 95% CI 1.43-8.39).
Conclusion: Neither symptoms of urinary nor anal incontinence differed at 6 months among women who had midpelvic and low pelvic aOVD. These findings are reassuring and need further studies at long-term to confirm these short-term data.