Is Vaginal Laxity Associated with Vaginal Parity and Mode of Delivery?

Introduction and hypothesis: Vaginal laxity (VL) is a common symptom of pelvic floor dysfunction. Although VL has become a frequent topic for research in the last decade, its pathogenesis is still not well understood. The objective was to determine whether vaginal parity or mode of delivery is associated with vaginal laxity.

Methods: This was a retrospective observational study involving women seen in a tertiary urogynecology clinic between May 2016 and November 2018 with symptoms of pelvic floor dysfunction. Patients underwent a standardized interview, clinical examination (POP-Q), and four-dimensional (4D) pelvic floor ultrasound (PFUS). Data regarding vaginal parity and the mode of delivery were based on patient-reported information. Archived 4D-PFUS volumes were analyzed offline to evaluate levator hiatal area on Valsalva.

Results: Data from 1,051 patients were analyzed. VL was reported by 236 women (23%) who were younger on average (mean age 54 vs 59 years, p < 0.001) and less likely to be menopausal (530 out of 815 [65.0%] vs.129 out of 236 [54.7%]), p = 0.004]. Symptoms of prolapse were much more common in the VL group (214 out of 236 [91%] vs 316 out of 815 [39%], p =  < 0.001) and on imaging mean levator hiatal area (HA) on Valsalva was larger (31 vs 26 cm², p = 0.01). Vaginal parity was associated with VL symptoms (235 out of 236 [99%] vs 767 out of 815 [94%], p = 0.008), but neither VL prevalence nor bother increased with higher parity. Women who delivered vaginally were three times more likely to complain of VL than those who delivered only by cesarean section.

Conclusions: Vaginal laxity was found to be more prevalent in vaginally parous women. This effect seems to be largely attributable to the first delivery. Instrumental delivery was not shown to increase association with VL compared with normal vaginal delivery.