Correlation between levator ani muscle injuries on magnetic resonance imaging and fecal incontinence, pelvic organ prolapse, and urinary incontinence in primiparous women

OBJECTIVE: The objective of the study was to correlate the presence of major levator ani muscle (LAM) injuries on magnetic resonance imaging (MRI) with fecal incontinence (FI), pelvic organ prolapse (POP), and urinary incontinence (UI) in primiparous women 6-12 months postpartum. STUDY DESIGN: A published scoring system was used to characterize LAM injuries on MRI dichotomously (MRI negative, no/mild vs MRI positive, major). RESULTS: Major LAM injuries were observed in 17 of 89 (19.1%) women who delivered vaginally with external anal sphincter (EAS) injuries, 3 of 88 (3.5%) who delivered vaginally without EAS injury, and 0 of 29 (0%) who delivered by cesarean section before labor (P = .0005). Among women with EAS injuries, those with major LAM injuries trended toward more FI, 35.3% vs 16.7% (P = .10) and POP, 35.3% vs 15.5% (P = .09), but not UI (P = 1.0). CONCLUSION: These data support the growing body of literature suggesting that both EAS and LAM are important for fecal continence and that multiple injuries contribute to pelvic floor dysfunction.