Is the endometriosis recurrence rate increased after ovarian hyperstimulation?

Objective: To test the hypothesis that the cumulative endometriosis recurrence rate (CERR) after fertility surgery for endometriosis stage III or IV is increased in women exposed to very high E-2 levels during ovarian hyperstimulation (OH) for IVF when compared with women exposed to less E-2 levels during OH for intrauterine insemination (IUI). Design: Retrospective cohort study including infertility patients with endometriosis stage III or IV. Setting: Leuven University Fertility Center, between 1990 and 2001. Patient(s): Patients (n = 67) with endometriosis stage III (n = 45) or IV (n = 22) who underwent reconstructive surgery and subsequently started fertility treatment with either IVF only (n = 39), both IVF and IUI in different cycles (n = 11), or IUI only (n = 17). Intervention(s): Life table analysis was used to calculate the CERR. Main Outcome Measure(s): The CERR based on histologic or cytologic proof of disease recurrence. Result(s): At 21 month after the start oh OH the overall CERR was 31% and was significantly lower in patients treated with IVF only (7%) or women treated with both IVF and IUI in different cycles (43%) than in those treated with IUI only (70%). At 36 months after the start of OH, the overall CERR was 63%. Conclusion(s): In contrast to our hypothesis, the results from this study showed that the CERR is lower after ovarian hyperstimulation for IVF than after lower-dose ovarian stimulation for IUI, suggesting that temporary exposure to very high E-2 levels in women during OH for IVF is not a major risk factor for endometriosis recurrence in women treated with assisted reproductive technology.