P-160: A Comparative Study of Luteal Estradiol Pre-Treatment in GnRH Antagonist Protocols AndIn Micro Dose Flare Protocols for Poor Responding Patients

Background: This study aims to verify if luteal estradiol pre-treatment improves IVF/ICSI outcomes in a GnRH antagonist protocol as compared to a micro dose GnRH agonist protocol in poor-responding patients. Materials and Methods: A total of 116 IVF/ICSI cycles were included in this prospective randomized clinical trial. The selected women were randomly assigned to receive an estradiol pre-treatment in a GnRH antagonist protocol (daily oral Estradiol Valerate 4 mg preceding the IVF cycle from the 21st day until the first day of the next cycle) or in a micro dose GnRH agonist protocol. Results: The patients in the luteal estradiol protocol required more days of stimulation (10.9 ± 1.6 vs. 10.2 ± 1.8) and a greater gonadotropin requirement (3247.8 ± 634.6 vs. 2994.8 ± 611 IU) ‚yet similar numbers of oocytes were retrieved and fertilized. There was no significant difference between the two groups in terms of the implantation rates (9.8% vs. 7.9%), and the clinical pregnancy rates per transfer (16.3% vs. 15.6%). Conclusion: This study demonstrates that the use of estradiol during a preceding luteal phase in a GnRH antagonist protocol can provide similar IVF outcomes when compared to a micro dose GnRH agonist protocol.