The impact of endometrioma and laparoscopic cystectomy on ovarian reserve and the exploration of related factors assessed by serum anti-Mullerian hormone: a prospective cohort study

BACKGROUND To evaluate the impact of the presence of endometrioma and laparoscopic cystectomy on ovarian reserve as assessed by serum anti-Müllerian hormone (AMH) level. In addition, factors related to the decline in ovarian reserve were analyzed. METHODS From June 2013 to January 2014, we prospectively included 40 women with endometriomas as the study group (group A), 36 women with tubal factor infertilities as control group 1 (group B) and 22 women with the other benign ovarian cysts as control group 2 (group C). The women with ovarian cysts underwent laparoscopic cystectomy. Serum AMH levels were determined preoperatively and at 1 month after surgery. RESULTS The endometrioma group had lower AMH levels (1.53 ± 1.37 ng/ml) compared with the other benign ovarian cyst group (2.20 ± 1.23 ng/ml) and the tubal factor infertility group (2.82 ± 1.74 ng/ml). The rate of serum AMH decline 1 month after surgery in the endometrioma group (0.62 ± 0.35) was larger than the decline in the other benign ovarian cyst group (0.32 ± 0.30). The preoperative AMH level showed a significant correlation with patient age (group A, r = -0.32; group B, r = -0.54; group C, r = -0.71); there was a statistically significant correlation between the rate of serum AMH decline and endometrioma diameter as well as with the preoperative serum AMH level. In addition, the rate of serum AMH decline was larger for bilateral endometriomas than for unilateral endometriomas, but there was no similar correlation in the other benign ovarian cyst group. The rate of AMH decline after surgery in the subgroup of >7 cm was significantly higher than in the subgroup of ≤7 cm. CONCLUSIONS Ovarian endometriomas per se may damage ovarian reserve, and cystectomy of endometriomas may cause greater damage to ovarian reserve compared with other benign ovarian cysts. The operation-related damage to the ovarian reserve was positively related to whether the endometriomas were bilateral, as well as cyst size (especially for cysts >7 cm), but was negatively related to the preoperative serum AMH level. Age was a negative factor that affected the ovarian reserve.