Urethral pressure reflectometry in women with pelvic organ prolapse: a study of reproducibility

The mechanism of continence in women with pelvic organ prolapse (POP) before and after surgery remains unknown. Urethral pressure reflectometry (UPR) separates women with stress urinary incontinence (SUI) from continent women by measuring urethral opening pressure at an abdominal pressure of 50 cmH₂O (P _{O-Abd 50}). UPR can help identify women with POP at risk of postoperative de novo SUI. The aim of this study was to investigate the reproducibility of UPR in women with POP.

Women with anterior or posterior vaginal wall prolapse were recruited for this prospective, observational study from our outpatient clinic. The women were examined with UPR on two occasions. Measurements were done at rest, and during squeezing and straining. Statistical analyses were performed using SAS 9.4. A Bland-Altman analysis with limits of agreement and coefficients of variation was used to determine the level of agreement between measurements. Paired t tests were used to estimate the difference; a two-tailed P value of <0.05 was considered significant.

We recruited 19 women with anterior vaginal wall prolapse and 11 women with posterior vaginal wall prolapse. There were no significant differences in the opening pressures at rest or during squeezing or in the values of P _{O-Abd 50}. P _{O-Abd 50} showed limits of agreement of 15.3 cmH₂O and a coefficient of variation of 9.9 %.

UPR was found to be a highly reproducible method in women with POP. UPR may be used in future studies to help reveal urodynamic features predictive of postoperative de novo SUI in women with POP.