A predictive model of choosing pessary type for women with symptomatic pelvic organ prolapse

OBJECTIVE: To investigate clinical factors including translabial ultrasound parameters, which are predictive for choosing pessary type (Ring or Gellhorn) in the fitting trial, and to establish a predictive model. METHODS: A retrospective study was conducted on symptomatic women with pelvic organ prolapse (POP) at the Pelvic Floor Disease Diagnosis and Treatment Center (Liaoning Province, China) between May 2018 and December 2020 who were successfully fitted with pessaries. This retrospective study was supplemented with a prospective cohort study on women seeking pessary for first-line treatment of POP at the above tertiary center between December 2020 and April 2021 for validation. Enrolled participants were grouped by their fitted type of pessary. Demographic and clinical parameters between groups, including pelvic organ prolapse quantification and translabial ultrasound, were analyzed using logistic regression. A receiver operating characteristic curve was calculated using predictive values obtained by regression as the predictor for choosing pessary type in the pessary fitting trial. RESULTS: The 181 participants included in the retrospective analysis were randomly divided into the “Development” and “Validation” datasets. In the “Development” set, multivariable logistic regression analyses showed that a younger age (odds ratio [OR]: 0.950; 95% confidence interval [CI]: 0.908-0.995; P = 0.026), a larger hiatal circumference on Valsalva (OR: 1.348; 95% CI: 1.103-1.647; P = 0.004), and a higher POP-Q stage (OR: 2.963; 95% CI: 1.210-7.255; P = 0.017) were independent predictors for successful fitting with the Gellhorn pessary. The predictive model was P = exp(Z)/[1 + exp(Z)], Z = −0.051 × Age (y) + 0.298 × hiatal circumference on Valsalva (cm) + 1.086 × pelvic organ prolapse stage (2, 3, or 4) − 5.490. The area under the receiver operating characteristic curves (AUC) was 0.776 (P < 0.001) and 0.705 (P < 0.001) based on the “Development” dataset and “Validation” datasets, respectively. The AUC was 0.815 (P < 0.001) based on the prospective cohort validation. CONCLUSIONS: For severe POP, women with younger age and larger hiatal circumference, Gellhorn pessaries should be their first choice instead of ring ones in pessary fitting trials.