Can levator avulsion be predicted antenatally?

Abstract

We sought to determine whether antepartum prediction of major levator trauma is feasible. A prospective longitudinal study was undertaken on 488 pregnant nulliparous women seen between 36-38 weeks and again 4 months after delivery. All underwent an interview and 4-dimensional transperineal ultrasound. Diagnosis of levator trauma (avulsion) on tomographic ultrasound was correlated with predelivery demographic variables and ultrasound parameters. In all, 367 women returned for postpartum assessment after normal vaginal delivery (n = 187), vacuum/forceps (n = 54), and cesarean section (n = 126). Avulsion was diagnosed in 34 vaginally parous women (14%). Maternal age, family history of cesarean section, hiatal dimensions, levator muscle strain, bladder neck descent, and subpubic arch angle were not associated with avulsion. The only predictor identified was a lower body mass index (P = .005). Antepartum prediction of major levator trauma may be difficult or impossible. Future studies should focus on modification of current obstetric practices and antepartum interventions applicable to the general population.