Benefits of minimal ethanol volume and retention without removal in transvaginal ethanol sclerotherapy for endometriomas

Abstract Purpose This study aims to introduce an effective protocol for transvaginal ethanol sclerotherapy, focussing on the aspiration of viscous cystic content and the amount of ethanol instilled in the cystic cavity according to cyst size. Methods We retrospectively reviewed the medical records of 90 women who underwent transvaginal ethanol sclerotherapy from 2015 to 2022 at Good Moonhwa Hospital, Busan, Republic of Korea. The volume of ethanol used for sclerotherapy was determined based on the initial volume of aspirated cystic content, with a target limit of 30 cc, and the injected alcohol was retained within the cystic cavity. All patients were followed up on postoperative days 1 and 2, at 2 weeks, 4 weeks, 3 months, 6 months, 12 months, and every 6 months thereafter to assess the ovary, AMH level, complications, recurrence, and pregnancy outcome. Results The cyst size was 5.07 ± 1.56 cm. AMH levels increased in 22 cases (27.4%) and decreased in 68 cases (75.6%). Among the 68 cases that decreased, 38 cases (55.9%) showed a mild decrease of less than 30%. The change rates in AMH levels did not significantly correlate with cyst size, aspirated cyst volume, alcohol instillation volume, operation time, recurrence rate, or pregnancy outcome. The volume of alcohol instilled significantly correlated with operation time. Of the 44 patients (78.9%) who wished to conceive, 17 (38.6%) became pregnant (12 spontaneously and 5 via IVF-ET). Recurrence occurred in 6 cases (6.67%). Conclusion This study demonstrates that our protocol for ethanol sclerotherapy not only significantly reduces the recurrence rate but also preserves ovarian reserve, as reflected by the minimal impact on AMH.