Evaluation of factors predicting diminished ovarian reserve before and after laparoscopic cystectomy for ovarian endometriomas: a prospective cohort study

BACKGROUND Ovarian endometriomas affect a substantial proportion of women of reproductive age who may have a potential risk of diminished ovarian reserve (DOR) after ovarian cystectomy. Here, we investigated the risk factors for pre-surgical DOR in patients with ovarian endometriomas and for DOR after laparoscopic ovarian cystectomy for endometriomas and evaluated the feasibility of the pre-surgical prediction of post-surgical DOR based on the Bologna criteria. METHODS A total of 143 patients with ovarian endometriomas who underwent laparoscopic cystectomy from January 2009 to May 2015 at our hospital were prospectively enrolled and evaluated. Serum anti-Müllerian hormone (AMH) concentrations were measured pre-surgically and at 3 and 6 months after surgery. In accordance with the Bologna criteria, the patients whose AMH concentrations were <1.1 ng/mL before surgery and 3 or 6 months after surgery were classified into pre- and post-surgical adverse DOR (aDOR) groups, respectively. RESULTS Thirty-one (21.7 %) of 143 patients were classified as pre-surgical aDOR. Patient age and serum follicle-stimulating hormone level were significantly positively correlated with pre-surgical aDOR [odds ratios (ORs), 1.26 and 1.16; p < 0.001 and p = 0.003, respectively]. Among the remaining 112 patients, 38 patients (33.9 %) had post-surgical aDOR 3 and 6 months after surgery. Bilateral cystectomy was positively correlated with post-surgical aDOR (at 3 months: OR, 4.7; p = 0.001; at 6 months: OR, 3.71; p = 0.006); conversely, pre-surgical serum AMH concentrations were negatively correlated with post-surgical aDOR (at 3 months: OR, 0.65; p = 0.005; at 6 months: OR, 0.43; p < 0.001). The optimal cut-off point of pre-surgical AMH concentrations for predicting aDOR at 3 and 6 months in the patients undergoing unilateral cystectomy was 2.1 ng/mL. In contrast, the optimal cut-off points at 3 and 6 months in the patients undergoing bilateral cystectomy were 3.0 and 3.5 ng/mL, respectively. CONCLUSIONS Our data suggest that the pre-surgical serum AMH concentrations and bilateral cystectomy are significant factors for the risk of aDOR following surgery and that predicting post-surgical aDOR according to the Bologna criteria could be feasible using pre-operative measurements of serum AMH concentrations.