Levator trauma after vaginal delivery.

OBJECTIVE To date, the evidence on pelvic floor injury in labor remains sketchy due to a lack of prospective studies comparing pelvic floor imaging before and after childbirth. We intended to define the incidence of major trauma to the pubovisceral muscle. METHODS A total of 61 nulliparous women were seen at 36-40 weeks of gestation in a prospective observational study. The assessment included an interview and 3-dimensional translabial ultrasound and was repeated 2-6 months postpartum. RESULTS Fifty women (82%) were seen postpartum. Of the 39 women delivered vaginally, levator avulsion was diagnosed in 14 (36%, 95% confidence interval 21-51%). Among those delivered vaginally, there were associations with higher maternal age (P = .10), vaginal operative delivery (P = .07), and worsened stress incontinence postpartum (P = .02). CONCLUSIONS Avulsion of the inferomedial aspects of the levator ani from the pelvic sidewall occurred in approximately one third of all women delivered vaginally and was associated with stress incontinence 3 months after childbirth.