Clinical outcomes of cavaterm thermal balloon endometrial ablation in women with refractory abnormal uterine bleeding: a multicenter retrospective cohort study

Endometrial ablation is an established minimally invasive alternative to hysterectomy for women with refractory non-structural abnormal uterine bleeding (AUB) who have completed childbearing. Despite the growing clinical adoption of thermal balloon systems, multicenter outcome data from Middle Eastern populations remain limited. This study evaluated the clinical outcomes and predictors of treatment success following Cavaterm thermal balloon endometrial ablation in Iranian women with refractory AUB. This retrospective cohort study was conducted at three tertiary teaching hospitals affiliated with Tehran University of Medical Sciences between March 2016 and March 2024. All consecutive women who underwent Cavaterm ablation for refractory AUB were included. Patients were contacted at a minimum of six months post-procedure via structured telephone interview. Menstrual outcomes were classified as amenorrhea, hypomenorrhea, eumenorrhea, or persistent/recurrent abnormal uterine bleeding. Primary outcome was treatment success, defined as achievement of amenorrhea, hypomenorrhea, or eumenorrhea. Secondary outcomes included changes in hemoglobin level, anemia prevalence, ultrasonographic parameters, and rate of subsequent hysterectomy. Exploratory univariate analyses examined associations between demographic, clinical, and preoperative ultrasonographic variables and treatment success. Of 52 eligible patients, 46 completed follow-up and were included in the final analysis. Treatment success was observed in 33 patients (71.7%; 95% CI 56.8–82.3), comprising amenorrhea in 34.8%, hypomenorrhea in 19.6%, and eumenorrhea in 17.4%. Mean hemoglobin increased significantly from 10.3 to 12.2 g/dL ( p = 0.005), and anemia prevalence declined from 73.9% to 34.8% ( p = 0.004). Endometrial thickness decreased from 8.6 to 3.6 mm ( p = 0.005). Seven patients (15.2%; 95% CI 7.6–28.2) underwent subsequent hysterectomy; histopathology revealed adenomyosis in five of these seven specimens. No demographic or procedural variable was significantly associated with treatment success in univariate analysis. Cavaterm thermal balloon endometrial ablation achieves clinically meaningful reductions in menstrual bleeding and anemia in women with refractory AUB, including those with significant medical comorbidities. Among the small subgroup requiring hysterectomy, adenomyosis was the most common histopathological finding — a hypothesis-generating observation rather than a confirmed predictor of treatment failure. Prospective studies with standardized follow-up, validated outcome measures, and adequate statistical power are warranted to validate predictive models and optimize patient selection.