Prediction of treatment outcomes after global endometrial ablation.

OBJECTIVE To report rates of amenorrhea and treatment failure after global endometrial ablation and to estimate the association between patient factors and these outcomes by developing and validating prediction models. METHODS From January 1998 through December 2005, 816 women underwent global endometrial ablation with either a thermal balloon ablation or radio frequency ablation device; 455 were included in a population-derived cohort (for model development), and 361 were included in a referral-derived cohort (for model validation). Amenorrhea was defined as cessation of bleeding from immediately after ablation through at least 12 months after the procedure. Treatment failure was defined as hysterectomy or reablation for patients with bleeding or pain. Logistic and Cox proportional hazard regression models were used in model development and validation of potential predictors of outcomes. RESULTS The amenorrhea rate was 23% (95% confidence interval [CI] 19-28%) and the 5-year cumulative failure rate was 16% (95% CI 10-20%). Predictors of amenorrhea were age 45 years or older (adjusted odds ratio [aOR] 2.6, 95% CI 1.6-4.3); uterine length less than 9 cm (aOR 1.8, 95% CI 1.1-3.1); endometrial thickness less than 4 mm (aOR 2.7, 95% CI 1.2-6.3); and use of radio-frequency ablation instead of thermal balloon ablation (aOR 2.8, 95% CI 1.7-4.9). Predictors of treatment failure included age younger than 45 years (adjusted hazard ratio [aHR] 2.6, 95% CI 1.3-5.1); parity of 5 or greater (aHR 6.0, 95% CI 2.5-14.8); prior tubal ligation (aHR 2.2, 95% CI 1.2-4.0); and history of dysmenorrhea (aHR 3.7, 95% CI 1.6-8.5). After global endometrial ablation, 23 women (5.1%, 95% CI 3.2-7.5%) had pelvic pain, three (0.7%, 95% CI 0.1-1.9%) were pregnant, and none (95% CI 0-0.8%) had endometrial cancer. CONCLUSION Population-derived rates and predictors of treatment outcomes after global endometrial ablation may help physicians offer optimal preprocedural patient counseling. LEVEL OF EVIDENCE II.