One of the problems associated with endometriosis is its high recurrence rate. The aim of the study was to assess the risk factors which might contribute to the recurrence of endometrial cysts after their surgical removal. Material and Method: The study included 49 patients admitted to Division of Reproduction, between January 2000 and June 2004, due to endometrial cysts. Patients with more than a two-year follow-up after the initial surgery were retrospectively analyzed. The surgery constituted either an enucleation or an excision of the cyst after prior mobilization of the ovary from surrounding adhesions via laparoscopy or laparotomy. Ten independent factors which might have an impact on the endometriosis recurrence have been the subject of our investigation and analysis. Results: The overall rate of recurrence was 18% (9/49). The age of the patient (28.8+/-5,4 years for recurrent endometriosis vs 33.1+/-5,2 years without endometriosis recurrence OR 0.789 95% CI = 0.609-1.020 ,p <0.05) proved to be an essential factor responsible for a more frequent endometriosis recurrence. Contrarily, hand removal of cysts via laparoscopy (66.7% vs 90% of laparoscopies in patients with and without recurrence, respectively, OR= 0.018 ,95% CI =0.0003-0.982, p=0.049 ) and pregnancy after surgical treatment (47.5% in patients without recurrence vs 22% in patients with recurrence, OR = 0.046, 95%CI = 0.0144-0,152, p= 0.031) was associated with significantly less frequent recurrence of endometriosis. Conclusisons: 1. Young age of patients at the time of the first operation predisposes them to repeated appearance of endometrial cysts. 2. Laparoscopic removal of endometrial cysts and pregnancy after surgery decreases the risk of recurrence.