The Aetiology of Sensory Impairment in Pelvic Organ Prolapse: A Prospective Cohort Study

Women with pelvic organ prolapse (POP) have reduced vaginal sensation. Vaginal birth has been associated with both sensory nerve injury and prolapse. It is unclear whether the impaired vaginal sensation seen in POP is caused during childbirth or by the prolapsing tissues themselves.

The objective was to perform to our knowledge the first study to compare vaginal sensation between women with postnatal POP and women without postnatal POP. A prospective cohort study (Canadian task force classification II-2) of 124 primiparous women who underwent Pelvic Organ Prolapse Quantification examination and neurophysiology at 3 and 6 months postnatally was carried out. Women underwent vibration quantitative sensory testing for Aβ nerve function and stretch quantitative sensory testing for Aα nerve function. POP was defined a priori as the distal-most portion of the vaginal wall at or below the hymen.

There was no difference in age or BMI between women with POP and women without POP. Vaginal vibration and stretch sensation were reduced in women with POP compared with controls at 3 months postnatally (p = 0.021 and 0.007 respectively). At 6 months postnatally vibration sensation remained impaired in the POP group, whereas stretch sensation had recovered compared with the control group (p < 0.001 and 0.498 respectively).

Vaginal sensation was reduced in women with postnatal POP suggesting that childbirth might contribute to the impaired vaginal sensation seen in women with POP in later life. Further work is required to determine if the impairment persists and is the reason for impaired sensory function seen in women with POP in later life.