The presence of ovarian endometriomas is associated with a reduced responsiveness to gonadotropins

Objective To clarify whether the presence of ovarian endometriomas is associated with a reduced responsiveness to ovarian hyperstimulation. Design Observational study. Setting University teaching hospital. Patient(s) Women selected for in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) cycles who were found to have unilateral ovarian endometriomas and who did not undergo previous ovarian surgery. Intervention(s) Ovarian hyperstimulation using gonadotropins. Main Outcome Measure(s) Number of codominant follicles (mean diameter >15 mm) in the affected and in the contralateral intact gonads. Result(s) Thirty-six patients were enrolled. They underwent 56 IVF-ICSI cycles. The number of codominant follicles in the intact and affected ovaries were 4.0 ± 2.2 and 3.0 ± 1.7, respectively ( P =.01). This difference corresponded to a mean reduction (95% confidence interval [CI]) of 25% (6%–44%). This deleterious effect was more evident in women with larger cysts, in those with more than one cyst, and in those who were more responsive to ovarian hyperstimulation. Conclusion(s) The presence of ovarian endometriomas is associated with a reduced responsiveness to gonadotropins.