Post-operative oral contraceptive use reduces the risk of ovarian endometrioma recurrence after laparoscopic excision

The aim of this study was to evaluate the impact of post-operative oral contraceptives (OCs) use on the rate of recurrence after laparoscopic excision of ovarian endometrioma. In May 2005, we introduced a 'post-operative OC recommendation' for patients treated with laparoscopic excision of endometrioma. That is, at the time of the operation, we provided each patient with information about OC, known and possible benefits and risks and let her decide whether to take OC. A retrospective cohort study included 87 patients who underwent a laparoscopy after May 2005. The endometrioma recurrence rate at 24 months was compared between those who used OC for the entire follow-up period OC (n = 34) and all of the others (n = 53). We also performed logistic regression analysis to identify variables associated with recurrence. A before-after study included another 224 patients who underwent a laparoscopy before May 2005 and compared the recurrence rate before and after introduction of the 'post-operative OC recommendation'. The recurrence rate in those who used OC for the entire period was significantly lower than in the 'others' group (2.9 versus 35.8%, relative risk 0.082, 95% CI 0.012-0.58, P < 0.001). Post-operative OC was determined as an independent variable associated with lower recurrence (OR 0.054, 95% CI 0.007-0.429, P < 0.001). The overall recurrence rate in patients who underwent laparoscopy after the introduction of the 'post-operative OC recommendation' was significantly lower than that in patients who received laparoscopy before the introduction (18.6 versus 33.1%, relative risk 0.56, 95% CI 0.32-0.97, P < 0.05). Post-operative OC use reduces the risk of ovarian endometrioma recurrence after laparoscopic excision. This information will help in appropriate planning of pre- and post-operative management.