Hysterectomy Rate Following Endometrial Ablation in Ontario: A Cohort Analysis of 76,446 Patients.

Background: Endometrial Ablation (EA) is an alternative to hysterectomy for the management of abnormal uterine bleeding (AUB); however, it does not eliminate the need for future surgical re-intervention. Objectives: The primary objective of this study was to establish long-term clinical outcomes including the risk of hysterectomy in women who had undergone a primary EA. Materials and Methods: This is a retrospective population-based cohort study utilising administrative data from the Canadian province of Ontario. This study assesses patients undergoing surgery in a publicly funded health care system. Main outcome measures: We assessed women in Ontario undergoing a primary EA over a 15-year period. The primary outcome was hysterectomy within 5 years of primary EA. Secondary outcomes included myomectomy and repeat EA. All outcomes were also reported for 1, 3, 5, 10 and 15 years of follow-up. Logistic regression was used to establish predictors of hysterectomy within 5 years of primary EA. Results: A total of 76,446 primary EAs were evaluated from 2002-2017, with 16,480 (21.56%) undergoing a subsequent surgical intervention. The average age of primary EA was 43.8 (+/- 6.3) years. Within 5 years, the evaluable cohort was 52,464, with 8,635 (16.46%) of women having proceeded to hysterectomy, 664 (1.27%) to myomectomy, and 2,468 (2.8%) to repeat ablation. By 15-years follow-up, the evaluable cohort was 1,788, with 28.75% had undergone a hysterectomy, 2.01% a myomectomy, and 5.20% a repeat EA. On logistic regression analysis, advancing age at time of EA was associated with significantly decreased odds of hysterectomy (OR=0.94, 95% CI 0.935-0.944, p<.0001) as was increasing surgical experience (OR=0.997, 95% CI 0.994-1.000, p=.022). Conversely, complex diagnosis (OR=1.102, 95% CI 1.042-1.164, p<.0001) and previous abdominal surgery (OR=1.288, 95% CI 1.222-1.357, p<0.0001) were associated with increased risk of subsequent hysterectomy. Conclusion: Primary EA is associated with a high risk of progression to subsequent hysterectomy or other surgical intervention, without evidence of plateau of risk with long term follow-up. What is new?: This study has the longest follow-up assessing hysterectomy outcomes in women undergoing a primary EA, with 28.75% of women having undergone a hysterectomy within 15 years of their EA.