A comparison of MRI-based pelvic floor support measures between young and old women with prolapse

We sought to 1) test the hypothesis that young women (≤45 years) with pelvic organ prolapse have a higher prevalence of major levator ani muscle (LAM) defects than old women (≥70 years) with prolapse and 2) compare level II/III measurements between young and old women with prolapse and age-matched controls to evaluate age-related mechanistic differences in the disease process.

A secondary analysis examined four groups of parous women: young prolapse (YPOP, n = 17); old prolapse (OPOP, n = 17); young controls (YC, n = 15); old controls, (OC, n = 13). Prolapse was defined as any compartment at or beyond the hymen with vaginal bulge symptoms. Genital hiatus (GH) was measured on clinical exam. Major LAM defects and level II/III measurements (UGH: urogenital hiatus, LA: levator area, and apex location) were assessed on MRI at rest and strain, and the difference (Δ) between measurements calculated. Principal component analysis was used to evaluate levator plate (LP) shape.

Major LAM defects occurred in 42% of YPOP and 47% of OPOP (p > .99). GH_rest was 1.5 cm larger in OPOP versus YPOP (p < .001) and 2 cm larger in OPOP versus OC (p < .001). Regardless of prolapse status, LA_rest and UGH_rest on MRI increased with age. YPOP had larger ΔLA (p = .04), ΔUGH (p = .03), and Δapex than OPOP (p = .01). Resting LP shape was more dorsally oriented in OPOP versus YPOP (p = .02) and OC versus YC (p = .004).

Prolapse in young women cannot be solely explained by a higher LAM defect prevalence. GH size and other measures of level II/III pelvic support worsen with age regardless of prolapse status.