Ethanol sclerotherapy for ovarian endometrioma - a systematic review and narrative synthesis

OBJECTIVE: The aim of this review was to evaluate the efficacy and safety of ethanol sclerotherapy (EST) for ovarian endometriomas, regarding the risk of recurrence, impact on ovarian reserve, and comparison with laparoscopic cystectomy. Additionally, we evaluated whether the available studies assessed the impact of this method on the patients' quality of life using validated questionnaires. METHODS: A total of 27 studies (2009-2025; N = 1,936) were included, consisting of two randomized controlled trials (RCTs) and 25 observational studies. Risk of bias was assessed using the Cochrane RoB 2 and ROBINS-I tools. The primary outcomes were recurrence rate and quality of life; the secondary outcome was the change in anti-Müllerian hormone (AMH) levels. RESULTS: Recurrence rate (0-48.6%) varied according to follow-up duration and treatment technique. Data suggest a benefit of the retention protocol (exposure ≥ 10 minutes) compared to simple irrigation. In the single RCT comparing EST and cystectomy, no significant difference in recurrence was found after 12 months (48.6 vs. 42.9%). Although surgery resulted in a decline in AMH levels, these remained largely stable following sclerotherapy (reported in 15 studies). No study evaluated quality of life using validated tools. The quality of evidence was limited by the predominance of observational studies with a risk of bias. CONCLUSION: EST represents a promising alternative to surgery, with a more favorable impact on ovarian reserve. The efficacy of recurrence prevention is variable depending on the duration of ethanol exposure. Given the methodological limitations and absence of quality of life data, findings must be interpreted with caution. Further RCTs, including quality of life assessment, are necessary to confirm clinical benefit.