Vaginal parturition decreases recurrence of endometriosis

Objective: To evaluate the role of parturition in the recurrence of endometriosis. Design: Retrospectively analyzed, prospectively obtained data. Setting: Unit of Physiopathology of Reproduction, Health Care Unit of Rimini, and University of Bologna Cervesi General Hospital, Cattolica, Italy. Patient(s): Three hundred forty-five patients with stage II-IV endometriosis, dysmenorrhea, and infertility were treated for endometriosis and divided into four groups according to parity and mode of parturition. Intervention(s): The patients were laparoscopically treated for endometriosis upon the occurrence and recurrence of the disease. Ultrasound measurements of the uterine internal ostium (IOS) were performed at each study interval. Main Outcome Measure(s): Degree of dysmenorrhea, occurrence and recurrence of endometriosis, and uterine IOS measurements were established and related to parity and mode of parturition. Result(s): After parturition, dysmenorrhea recurrence was significantly higher in nulliparous women than in women with vaginal parturition. The endometriosis recurrence rate was higher in women who did not have vaginal parturition. The IOS significantly enlarged after vaginal delivery but not after cesarean delivery. There were significant negative correlations between IOS and the recurrence of endometriosis and dysmenorrhea. Odds ratios indicated that as the IOS enlarged, the risk of recurrence decreased. Conclusion(s): Vaginal parturition plays a protective role in the recurrence of endometriosis. (Fertil Steril (R) 2010; 94: 850-5. (c) 2010 by American Society for Reproductive Medicine.)