Intraoperative Predictors of Long-term Outcomes After Radiofrequency Endometrial Ablation

Study Objective: To identify intraoperative predictors of radiofrequency ablation (RFA) failure after adjusting for clinical risk factors. Design: A cohort study (Canadian Task Force II-2). Setting: An academic institution in the Upper Midwest. Patients: Data were retrospectively collected from medical records of women who underwent RFA and who had a postprocedure gynecologic assessment between April 1998 and December 2011. Interventions: RFA. Measurements and Main Results: The primary outcome was RFA failure, which was defined as hysterectomy, repeat ablation, synechiolysis, or treatment with gonadotropin-releasing hormone analogue for postablation pain or bleeding. Cox proportional hazards regression was used to test the predictability of intraoperative variables on RFA failure with adjustment for baseline predictors. We created an RFA index to capture the procedure duration divided by the uterine surface area. One thousand one hundred seventy-eight women were eligible. The median age at ablation was 44 years (interquartile range, 40-48 years), and the median parity was 2 (interquartile range, 2-3). Dysmenorrhea and prior tubal ligation were reported in 37.1% and 37.2% of women, respectively. After adjustment for baseline characteristics, intraoperative predictors of failure were uterine sounding length >10.5 cm (adjusted hazard ratio [HR] = 2.58; 95% confidence interval [CI], 1.31-5.05), uterine cavity length >6 cm (adjusted HR = 2.06; 95% CI, 1.30-3.27), uterine width >4.5 cm (adjusted HR = 2.06; 95% CI, 1.29-3.28), surface area >25 cm² (adjusted HR = 2.02; 95% CI, 1.26-3.23), procedure time