A “freeze-all” strategy or GNRH agonist trigger and concomitant HCG in high responders: a retrospective cohort study

Abstract

To compare pregnancy rates and the incidence of OHSS in high responder women undergoing final oocyte maturation with GnRH agonist and concomitant use of 1500 IU hCG on the day of oocyte collection or “freeze-all” protocol. Retrospective cohort study. Women who had more than 15 follicles and/or estradiol level above 2500 pg/ml and less than 4000 pg/ml on the day of triggering were included. In group 1, a total of 58 patients, GnRH agonist (1 mg leuprolide acetate) was used for triggering with concomitant use of 1500 IU hCG on the day of oocyte collection and fresh embryo transfer was performed. In group 2, a total of 36 patients underwent GnRH agonist triggering and all embryos were cryopreserved at 2PN-stage. They had embryo transfer in a subsequent artificially prepared cycle. Patient’s age, number of oocytes collected, estradiol level on the day of triggering and fertilization rates were similar between the two groups. Two patients (3.4%) developed moderate OHSS in fresh cycle and none in the cryopreserved group. There were no significant differences in implantation (33.3% vs. 33.8%) and clinical pregnancy rates (44.8% vs. 52.7%) between fresh and frozen-thawed embryo transfer groups, respectively. Outcome of ICSI cycles with agonist triggering and concomitant use of 1500 IU hCG is similar to that obtained with the transfer of frozen-thawed embryos in high responders. However, the risk of moderate OHSS is higher.