A prospective randomized controlled trial comparing two groups of ICSI (intra-cytoplasmatic sperm injection) patients with a different form of triggering the final oocyte maturation has been performed. All patients received an ovarian stimulation for in vitro fertilisation (IVF) using an antagonist protocol using recombinant-FSH -(rec-FSH) and Ganirelix. 120 Patients were randomized into two groups with similar clinical parameters. The first group had triggering with hCG, whereas the second group received a combination of hCG + GnRH agonist (Gonadotropin Releasing Hormone). As the primary endpoint, the number of metaphase II oocytes were analysed, the secondary endpoints were the number of cumulus oocyte complexes (COC), the number of fertilized oocytes, embryo morphology, pregnancy rate and the number of cryopreserved embryos. The mean number of MII oocytes in the hCG triggered group was 9.2 compared with 10.3 in the hCG-GnRH agonist group. There was no statistically significant difference in the number of COCs or pregnancy rates. However, the number of patients who received at least one embryo of excellent quality was significantly higher (p = 0.001) in the group with the combined triggering (45 out of 61 patients or 73.8%) versus the group with hCG triggering alone (28 out of 59 patients or 47.5%). The number of cryopreserved embryos was also higher in this group.