Triggering with HCG or GnRH agonist in GnRH antagonist treated oocyte donation cycles: a randomised clinical trial

To compare donor and recipient outcome after inducing the final oocyte maturation with hCG or GnRH agonist in GnRH-antagonist treated oocyte donation (OD) cycles.

Two-hundred fifty-seven oocyte donors were enrolled to participate in a clinical trial in a private fertility centre. After stimulation with 225 IU rFSH and Cetrorelix 0.25 mg/day, 212 oocyte donors were randomised with sealed envelopes for triggering with recombinant hCG (Ovitrelle 250 microgr, n = 106) or a GnRH agonist (triptorelin 0.2 mg, n = 106).

The number of retrieved COCs (12 +/- 6.3 vs 11.4 +/- 6.4), mature oocytes (8 +/- 4.6 vs 7.5 +/- 4.1), the proportion of mature oocytes (67.2 +/- 20.4% vs 67.1 +/- 20.9%) and fertilisation rates (67.8 +/- 23.5% vs 71.1 +/- 22.1%) were comparable. Clinical, ongoing pregnancy and live birth rates were not statistically different in the corresponding recipient groups. Nine cases of mild and one case of severe OHSS occurred in hCG group, whereas no cases were detected in GnRH agonist group.

The findings of our RCT suggest that donor and recipient outcome are comparable in OD cycles triggered with hCG or a GnRH agonist. Furthermore, the risk of OHSS seems to be reduced considerably, therefore the combination of a GnRH antagonist protocol with GnRH agonist triggering constitutes a safe treatment option for egg-donors.