Endometrioma-related reduction in ovarian reserve (ERROR): a prospective longitudinal study

Objective: To evaluate whether endometrioma is associated with a progressive decline in ovarian reserve, and to compare the rate of decline with natural decline in ovarian reserve. Design: Prospective, observational study. Setting: Tertiary university hospital, endometriosis clinic. Patient(s): Forty women with endometrioma and 40 age-matched healthy controls. Intervention(s): Women with endometriomas who did not need hormonal/surgical treatment at the time of recruitment and were expectantly managed. Controls were age-matched, healthy women. All participants underwent serum antimullerian hormone (AMH) testing twice, 6 months apart. Sexually active patients with endometrioma also underwent antral follicle count. Main Outcome Measure(s): Change in serum AMH levels. Result(s): Median (25th-75th percentile) serum AMH level at recruitment was 2.83 (0.70-4.96) ng/mL in the endometrioma group and 4.42 (2.26-5.57) ng/mL in the control group. The median percent decline in serum AMH level was 26.4% (11.36%-55.41%) in the endometrioma group and 7.4% (-11.98%, 29.33%) in the control groups. Twenty-two women with endometrioma who had antral follicle count (AFC) had median AFC of 10 (8-12) at recruitment and 8 (6.3-10) at 6 months. Conclusion(s): Women with endometrioma experience a progressive decline in serum AMH levels, which is faster than that in healthy women. (C) 2018 by American Society for Reproductive Medicine.