Received October 23, 2019
Accepted April 30, 2020

Objective: In order to help make the dream of parenthood come true for oocyte acceptors, it is essential that the procedure is not dangerous or unpleasant for oocyte donors. The aim of this study was to identify differences in safety, efficacy and patient acceptability between a traditional stimulation antagonist protocol with recombinant-FSH (rFSH) with hCG-triggering, compared with an innovative antagonist protocol with corifollitropin alfa (Elonva®) plus GnRH agonist triggering in oocyte donors. Methods: A prospective longitudinal study was conducted at an in vitro fertilization center in Greece. The same eighty donors underwent two consecutive antagonist stimulation schemes. Primary outcomes were patient satisfaction (scored by a questionnaire) and delivery rate per donor. Secondary outcomes were mean number of cumulus-oocyte-complexes, metaphase II (MII) oocytes and ovarian hyperstimulation syndrome (OHSS) rate. Results: Donors reported better adherence and less discomfort with the corifollitropin alpha + GnRH agonist-triggering protocol (p<0.001). No significant differences were identified in the clinical pregnancy rate per donor (p=0.13), the delivery rates, the number of oocytes (p=0.35), the number of MII oocytes (p=0.50) and the number of transferred embryos, between the two protocols. However, the luteal phase duration was significantly shorter (p<0.001) in the corifollitropin alpha + GnRH agonist-triggering protocol. Moreover, three cases of moderate OHSS (3.75%) were identified after hCG triggering, whereas no case of OHSS occurred after GnRH agonist ovulation induction (p=0.25). Conclusion: The use of corifollitropin alpha combined with a GnRH agonist for triggering is a safe, effective and acceptable protocol for oocyte donors.