We sought to evaluate the cumulative recurrence rate of endometrioma after a second-line, conservative, laparoscopic endometriotic cyst enucleation and to analyze the factors that influence the recurrence of endometrioma.

A multicenter retrospective cohort study was performed at 3 gynecologic surgery centers from January 2000 through December 2010. Patients surgically treated by laparoscopic enucleation of endometriotic cysts on 2 previous occasions were selected. All patients were aged <40 years at the time of the primary surgery and were followed up for at least 6 months. Endometrioma recurrence was considered when transvaginal sonography indicated a cystic mass with a diameter of ≥20 mm.

In total, 183 patients were followed up for 33.2 ± 27.7 months (range, 6–121 months). Thirty-eight (20.8%) patients experienced recurrence after the second-line surgery and 24 (13.1%) patients underwent a third surgery. The median time to recurrence was 24 ± 3.36 months (SEM) (range, 3–72 months). The cumulative recurrence rates per patient at 12, 24, 36, and 60 months after the second-line surgery were 7.7%, 13.7%, 21.3%, and 37.5%, respectively. After multivariate analysis and analysis of covariance, the revised American Fertility Society score and stage were significantly higher in patients who experience a third recurrence of endometrioma.

The cumulative recurrence rate of ovarian endometrioma after a second-line surgery appears to be correlated to the duration of follow-up. Severe endometriosis at the second-line surgery seems to be a factor associated with a high recurrence risk. Physicians should be cautious with regard to the postoperative management of these patients.