Perineal and vaginal tears are clinical markers for occult levator ani trauma: a retrospective observational study

Levator avulsion has been shown to be associated with anterior and central compartment prolapse and is a risk factor for prolapse recurrence. Diagnosis in the delivery room is usually impossible, as levator avulsion is commonly occult. The objective of this study was to determine if vaginal and major perineal tears are clinical markers of levator trauma as diagnosed by four-dimensional (4D) translabial ultrasound 3-6 months postpartum.

This was a retrospective observational study using data obtained in two perinatal trials. A total of 774 women seen, on average, 5 (range, 2.3-22.4) months after their first delivery of a term singleton cephalic baby underwent a standardized interview, clinical assessment and 4D translabial ultrasound examination. Clinical data were obtained from the institutional obstetric database, including information on vaginal and perineal tears. Levator avulsion was diagnosed using tomographic ultrasound, with operators blinded to the clinical data.

Both third- and fourth-degree perineal tears and vaginal sidewall tears were independently associated with levator avulsion (P = 0.004 and P = 0.012, respectively). The odds ratio for avulsion in women suffering from such overt trauma was 3.44 (95% CI, 1.47-8.03) for third-/fourth-degree perineal tears and 3.35 (95% CI, 1.30-8.61) for vaginal sidewall tears.

Vaginal sidewall and third-/fourth-degree perineal tears were found to be independent clinical indicators of an increased risk of levator trauma, as diagnosed by 4D translabial ultrasound 3-6 months postpartum. Such clinical markers may become useful in the identification of women at high risk of levator trauma and future pelvic floor disorders.