Association between levator ani avulsion and urinary incontinence in women: A systematic review and meta-analysis

Background: Urinary incontinence is a bothersome symptom. Although the relationship between stress urinary incontinence (SUI) and vaginal delivery is established, the pathology underlying SUI after vaginal birth remains to be elucidated.

Objectives: To determine whether levator ani muscle avulsion predisposes for SUI in women.

Search strategy: Pubmed and Embase were searched for terms and their variations "levator ani muscle avulsion" and "urinary incontinence", from inception until 5 November 2019.

Selection criteria: Inclusion criterion: studies describing the relationship between urinary incontinence and levator ani muscle avulsion in women at least 1 year after delivery. Exclusion criterion: studies only analyzing the urethral sphincter or hiatus dimensions.

Data collection and analysis: Odds ratios were used and if not available, were calculated as means of data synthesis, adjusted odds ratios if presented by the study, random-effects model to compute a pooled estimate.

Results: Seven studies were included, accounting for 2388 women. Comparing women with and without levator ani muscle avulsion, the overall odds ratio for SUI is 0.87 (95% confidence interval 0.56-1.34), and after adjustment for possible confounders was 0.72 (95% confidence interval 0.40-1.30).

Conclusion: There is no relationship between levator ani muscle avulsion and SUI in women.