Corifollitropin alfa followed by rFSH in a GnRH antagonist protocol for poor ovarian responder patients: an observational pilot study.

To identify whether women with poor ovarian response may benefit from treatment with corifollitropin alfa in a GnRH antagonist protocol.Retrospective pilot study.University-based tertiary care center.Poor ovarian responders fulfilling the Bologna criteria developed by European Society for Human Reproduction and Embryology Consensus Group.Corifollitropin alfa (150 μg) followed by 300 IU rFSH in a GnRH antagonist protocol.Endocrinologic profile and ongoing pregnancy rates.Among 43 women treated with corifollitropin alfa, mean E(2) levels showed an increasing pattern during the follicular phase, reaching 825 ng/L on the day of hCG administration, whereas FSH values showed a marked increase during the first 5 days, reaching a mean value of 35 IU/L and remaining above 20 IU/L during the late follicular phase. Cycle cancellation rate was 32.6% and embryo transfer rate 53.3%. Five patients (11.7%) had a positive hCG test and three (7%) had an ongoing pregnancy. Ongoing pregnancy rates were 11.1% per oocyte retrieval and 13% per embryo transfer. Ongoing pregnancy rates per patient did not significantly differ compared with a cohort of patients treated during 2011 with the standard protocol for poor responders in our center (short agonist-hMG) (7% vs. 6.3%).Treatment of poor ovarian responders, as described by the Bologna criteria, with corifollitropin alfa in a GnRH antagonist protocol results in low pregnancy rates, similarly to conventional stimulation with a short agonist protocol.