Pelvic Floor Dysfunction After Obstetric Anal Sphincter Injuries: A Prospective Cohort Study

INTRODUCTION AND HYPOTHESIS: Obstetric anal sphincter injuries (OASIS) compromise pelvic floor function and quality of life; prospective evidence from low-resource settings remains scarce. We hypothesised that OASIS would be associated with worse sexual function and greater pelvic floor distress than controls over the first 6 months postpartum. METHODS: Prospective cohort study conducted at a tertiary maternity unit in [Fortaleza, Ceará, northeastern Brazil] (2022-2024). Women with OASIS (n = 22) and controls without perineal injury (n = 69) were assessed using the PFDI-20, PFIQ-7, FSFI, and SF-36 at T0 (immediate postpartum), T1 (3 months), and T2 (6 months). STATISTICAL ANALYSIS: Mann-Whitney and Friedman/Dunn tests (α = 0.05). RESULTS: Ninety-one women were enrolled (OASIS incidence 1.2%); factors associated with OASIS were nulliparity, vacuum-assisted delivery, elevated neonatal birthweight, and epidural analgesia. Sexual dysfunction occurred in both groups throughout follow-up; the OASIS group had worse Arousal and Pain scores at T2 (p = 0.013; p = 0.037). On the PFDI-20, bowel and urinary symptoms were more severe in the OASIS group at T1 (p = 0.014; p = 0.005), with a difference in total score at T2 (p = 0.048). On the PFIQ-7, greater symptom impact was observed in the OASIS group at T1 (p = 0.035) and T2 (p = 0.017). Overall quality of life (SF-36) was similar between groups. CONCLUSIONS: OASIS were associated with worse sexual function and pelvic floor distress than controls from 3 months postpartum, confirming the study hypothesis; overall quality of life was similar between groups. Structured multidisciplinary postpartum follow-up addressing sexual function and pelvic floor rehabilitation is warranted for women with OASIS in low-resource settings.