[Impact of obstetric lesions of the levator ani on anal continence].

Introduction: Vaginal delivery induces avulsion type muscle lesions and minor stretching of the levator ani muscle (LAM). Sharing the same risk factors as obstetric anal sphincter injury (OASIS), they can be concomitant. OASIS are the first risk factor for anal incontinence (AI) in women. The role of levatorian lesions in the genesis of AI is controversial.
Objective: This is a systematic review without meta-analysis aimed at clarifying the impact of LA lesions on anal continence.
Method: According to PRISMA recommendations, carrying out a bibliographic search (2000-2022) on PubMed with the keywords: "levator ani" "anal incontinence" "obstetric trauma" and on Science Direct with the keywords "levator ani", "avulsion", "anal incontinence". One hundred and eighty articles were identified, 16 were selected.. The level of evidence was determined using the Newcastle Ottawa Scale.
Results: According to the different authors, the prevalence of avulsion varied from 15% to 32.2% among women who gave birth vaginally, women with LA lesions presented more LOSA (29.4% to 37.5% of patients with OASIS also had an LA lesion). For AI, LA avulsions are not an independent risk factor but are, in the presence of OASIS, an aggravating factor (OR, 23.3, 95% CI, 2.0-267.6). Double lesions would be at greater risk of long-term AI (P<0.001).
Conclusion: LA lesions are not an independent factor of AI, although their prevalence is higher in the population of anal incontinent women; they are more frequent in women with OASIS and in this population, they are an aggravating factor for AI and a risk factor for long-term AI.
(Copyright © 2022. Published by Elsevier Masson SAS.)