Can women without visible pubococcygeal muscle in MR images still increase urethral closure pressures?

Objective The purpose of this study was to determine if the ability to increase maximum urethral closure pressure (MUCP) with a pelvic muscle contraction is impaired in women without pubococcygeal muscle (PCM). Study design This was a cross-sectional study of continent women comparing those with (n = 28) and those without (n = 17) PCM as identified by MR scans. A pelvic muscle contraction was performed simultaneously with recordings of urethral and bladder pressures. Results Eighty-six percent of the women with PCM compared with 41% of the women without could volitionally increase (>5 cm H2O) their MUCP. Those with PCM generated a mean intraurethral pressure rise of 14.0 (10.8) cm H2O, compared with 6.2 (8.7) cm H2O in those without (P = .015). Among women who could produce a visible pressure rise, there was not a statistically significant difference between groups (with PCM = 17.2 [7.8] cm H2O; without PCM = 14.7 [7.5] cm H2O; P = .457). Conclusion Selective women without visible PCM can increase MUCP.