Aims: To describe the vaginal pressure profile in asymptomatic nulliparous women.
Methods: Fourteen nulliparous women without symptoms of anal or urinary incontinence were studied with vaginal manometry. A rapid pull-through technique utilized a four-channel water-perfused catheter on a motor-driven puller to create a pressure profile for each subject. The profiles were measured with the subject at rest and during a sustained contraction of the levator ani muscle. The individual subject's pressure profiles were averaged to create a composite profile at rest and during squeeze.
Results: The vaginal pressure profile at rest and during squeeze contains three pressure zones: proximal, mid, and distal. The pressure is highest in the mid pressure zone and was labeled as the vaginal high-pressure zone. In the vaginal high-pressure zone, the maximum pressure during squeeze is significantly higher than the maximum pressure at rest (P < 0.05). The length of the high-pressure zone is longer during squeeze as compared to rest (P < 0.05). The maximum pressures exhibit circumferential asymmetry with the pressures in anterior and posterior directions being significantly higher than those in the lateral directions (P < 0.05).
Conclusions: The vaginal pressure profile is more complex than previously described. Understanding of the vaginal pressure profile is crucial when employing vaginal manometry to assess pelvic floor muscle strength or as a surrogate for intra-abdominal pressure.