Received December 21, 2020
Accepted June 29, 2021

Objective: This study aims to assess the effect of endometrioma surgery on ovarian reserve by measuring anti-mullerian hormone (AMH) levels. Methods: Systematic review of literature and meta-analysis of observational studies and randomized clinical trials in English using MEDLINE, SCOPUS and Cochrane (1982-2019). We included studies that reported AMH values ​​in the pre and post-operative period of patients undergoing laparoscopic surgery for endometrioma. Preoperative AMH was defined as the baseline AMH; short term AMH measured less than or equal to one month after surgery; medium-term between one and six months after surgery; and long-term AMH measured within a period equal to or greater than 6 months after surgery. Results: 36 studies met the inclusion criteria. A significant decrease in short, medium and long-term post-operative AMH were observed when compared to the baseline AMH. However, there were no differences between the short and long-term post-operative AMH, suggesting a non-significant recovery after one year of follow-up. A significant decrease in post-operative AMH was observed in bilateral endometriomas compared to unilateral ones. In addition, patients with endometriomas presented a significant decline in post-operative AMH compared to patients with other benign ovarian pathology. The decrease in post-operative AMH is significantly greater in bilateral cystectomy when compared with vaporization with bipolar energy or laser. There was also observed a greater decrease in post-operative AMH with bipolar energy hemostasis compared to suture and hemostatic agents. These results should be taken with caution due to the high heterogeneity of the studies analyzed. Conclusions: Endometrioma surgery has a deleterious effect on short, medium, and long-term post-operative AMH. Bilateral endometriomas and those greater than 7 cm are associated with a greater decrease in AMH. The mechanical resection of healthy tissue and the inflammatory damage on the ovarian cortex would explain the diminishing of ovarian reserve.