RESUMEN
INTRODUCTION AND HYPOTHESIS: The objective was to assess if specific reasons for unsuccessful pessary fitting have different predictive parameters. METHODS: This is a prospective observational case-control study of women with symptomatic pelvic organ prolapse (POP) choosing pessary treatment. All women underwent an interview, clinical examination, and 3D/4D transperineal ultrasound (TPUS). Groups were defined based on fitting outcome: successful, pessary dislodgment, failure to relieve POP symptoms, pain/discomfort, increased/de novo urinary incontinence, or other reasons. Clinical, demographic, and TPUS parameters were assessed in the prediction of different reasons for unsuccessful fitting and receiver operating characteristic (ROC) curves were constructed. RESULTS: A total of 162 women were assessed and 130 were included. Levator hiatal area (HA) on maximum Valsalva divided by ring pessary size ("Valsalva HARP ratio") was a predictor of unsuccessful fitting (OR 3.00, 95% CI 1.15-7.81, p = 0.025) with an area under the ROC curve (AUC) of 0.62 (95% CI 0.50-0.74, p = 0.04). Predictors of pessary dislodgment were: complete avulsion (OR 24.20, 95% CI 2.46-237.84, p value 0.01) and Valsalva HARP ratio (OR 2.94, 95% CI 1.32-6.55, p value 0.01) with an area under the ROC curve (AUC) of 0.92 (95% CI 0.84-0.99, p = 0.00). No significant parameter was identified in the prediction of pain/discomfort. Solitary predominant posterior compartment POP was a predictor of failure to relieve POP symptoms (OR 20.00, 95% CI 3.48-115.02, p value 0.00; AUC 0.75, 95% CI 0.53-0.98, p = 0.03). CONCLUSION: Complete avulsion and a small ring pessary with respect to the levator HA in Valsalva are predictors of pessary dislodgment, whereas solitary predominant posterior compartment POP is a predictor of failure to relieve POP symptoms.