Objective To investigate the impact on ovarian reserve of second laparoscopic surgery for recurrent unilateral endometriomas. Design Case-control study. Setting University teaching hospital. Patient(s) This study included patients who underwent stripping of endometriomas (diameter ≥4 cm) and were followed-up at our institution. Case subjects had second surgery for recurrent unilateral endometriomas (n = 18); control subjects had no recurrence and no second surgery (n = 18). Intervention(s) This case-control study was based on a retrospective analysis of a prospectively collected database including patients who underwent surgery for endometriomas at our institution. Main Outcome Measure(s) The primary outcome of the study was to assess the changes in antimüllerian hormone (AMH) levels in each study group and between the two study groups. The secondary outcomes of the study were to assess the changes in basal FSH, antral follicle count (AFC), and ovarian volume in each study group and between the two study groups. Result(s) In both study groups, primary surgery decreased AMH, increased basal FSH, and decreased the AFC of the operated ovary. Before second surgery, case subjects had AMH, basal FSH, and AFC similar to control subjects. After second surgery, case subjects had lower AMH, higher basal FSH, and lower AFC of the affected ovary than before surgery; the volume of the operated ovary was lower than that of the contralateral ovary. Conclusion(s) The laparoscopic stripping of recurrent ovarian endometriomas is associated with a high risk of ovarian reserve damage and ovarian failure. Clinical Trial Registration Number NCT02047838.