The maternal pelvic floor and labor outcome.

Vaginal birth is the major cause of pelvic floor damage. The development of transperineal ultrasound has improved our understanding of the relationship between vaginal birth and pelvic floor dysfunction. The female pelvic floor dimensions and function can be assessed reliably in pregnant women. Maternal pushing associated with pelvic floor muscle relaxation is the central requirement of vaginal birth. Many studies have evaluated the role of the pelvic floor on labor outcomes. Smaller levator hiatal dimensions and incomplete or absent levator ani muscle relaxation seem to be associated with a longer duration of the second stage of labor and a higher risk of cesarean and operative deliveries. Here, we presented an overview of the current knowledge of the correlation between female pelvic floor dimension and function, as assessed by transperineal ultrasound, and labor outcome.