A prospective cohort study of pelvic support changes among nulliparous, multiparous, and pre- and post-menopausal...

To evaluate whether vaginal delivery affects maternal pelvic support beyond the puerperium by comparing pelvic support changes between nulliparas and multiparas, and whether menopause predisposes women to develop prolapse that protrudes beyond the hymen by comparing its occurrence between pre- and post-menopausal subjects.

Women who presented to our gynecology clinic for routine care and returned for follow-up after 36 ± 3 months were evaluated for pelvic support changes using the Pelvic Organ Prolapse Quantification, which measured changes in 1-cm increments. Exclusion criteria were women who were seen in the urogynecology clinic or had hysterectomy, vaginal repair, continence procedure, childbirth during the study period, or radiation therapy.

The proportion that experienced a 1-cm (21/101 vs. 27/164, p=0.374) and at least a 2-cm (5/101 vs. 9/164, p=0.849) descent of the leading edge of prolapse was similar between our 101 nulliparous and 164 multiparous subjects. At the initial examination, nine multiparas and one nullipara had prolapse outside the hymen (9/164 vs. 1/101, p=0.056). The proportion that developed pelvic support defect, which protruded beyond the hymen, was similar between the two groups (1/100 vs. 5/155, p=0.243). Eighty-five of our 265 subjects were post-menopausal while 180 were pre-menopausal. The proportions that developed a 1-cm (18/85 vs. 30/180, p=0.374) and at least a 2-cm (7/85 vs. 7/180, p=0.140) descent of the leading edge of prolapse were similar between the two groups. Eight post-menopausal and two pre-menopausal women had prolapse outside the hymen at the initial examination (8/85 vs. 2/180, p=0.002). More post-menopausal subjects developed support defect, which protruded beyond the hymen, than their pre-menopausal counterparts (5/77 vs. 1/178, p=0.010). Logistic regression showed that menopause (p=0.019) is an independent risk factor for developing prolapse which protruded outside the hymen, while parity (p=0.168) and interaction between menopause and parity (p=0.606) are not significantly associated with its occurrence.

Vaginal birth has little effect on the pelvic support changes beyond the puerperium while menopause predisposes women to prolapse their pelvic organ outside the hymen.