Antagonist/letrozole protocol in poor ovarian responders for intracytoplasmic sperm injection: a comparative study with the microdose flare-up protocol

Objective: To compare the effect of the GnRH antagonist/letrozole protocol (AL) with the microdose GnRH agonist flare-up (MF) protocol in poor ovarian responders for intracytoplasmic sperm injection (ICSI). Design: Retrospective, case-control study. Setting: Anatolia Women and IVF Center. Patient(S): Eight hundred eighty-five consecutive patients (1383 cycles) predicted to have or with a history of poor ovarian response who were undergoing ICSI were enrolled. The MF protocol was used in 673 patients (1026 cycles), and the AL protocol was used in the remaining 212 patients (357 cycles). Intervention(s): Controlled ovarian hyperstimulation and ICSI. Main Outcome Measurement(s): Cycle cancellation rate, number of oocytes retrieved, fertilization rate, embryo quality, clinical pregnancy, and implantation rates. Result(S): The total gonadotropin consumption, duration of stimulation, E(2) level on the day of hCG administration, and number of oocytes retrieved were significantly lower with the AL protocol compared with the MF protocol. However, the fertilization rate and the rate of at least one top-quality embryo transferred were higher with the AL compared with the MF protocol. The clinical pregnancy rates were comparable between the two groups. The implantation rates with the MF and AL protocols were 9.8% and 14.5%, respectively. Conclusion(s): The GnRH AL protocol is an effective protocol that may be used in poor ovarian responders for ICSI. (Fertil Steril (R) 2009;92:231-5. (C) 2009 by American Society for Reproductive Medicine.)