Application of the Fertilase-laser system versus the conventional mechanical method to immobilize spermatozoa for intracytoplasmic sperm injection. A randomized controlled trial.

A randomized controlled trial was set up to test the hypothesis that the fertilization rate of oocytes after intracytoplasmic sperm injection (ICSI) is higher after immobilization of the spermatozoa with the Fertilase-laser system technology than after immobilization of the spermatozoa with the conventional mechanical method. Metaphase II oocytes were injected with spermatozoa that were immobilized with the conventional mechanical method (group A, n=177) or with spermatozoa that were immobilized with the Fertilase-laser system technology (group B, n=179). The fertilization rate per successfully injected oocyte was comparable in group A (62.6%; 92/147) and in group B (56.3%; 89/158)(p=0.3). No difference could be observed in fertilization rates of oocytes injected with spermatozoa that were immobilized with the Fertilase-laser system technology compared to spermatozoa immobilized with the conventional mechanical method.

A prospective randomized study: day 2 versus day 5 embryo transfer.

BACKGROUND: This randomized controlled study was performed in an unselected IVF/ICSI population to test the hypothesis that blastocyst transfers result in higher clinical pregnancy rates (CPR) per oocyte retrieval when compared with day 2 transfers. METHODS: Blind randomization for transfer on day 2 (group 1) or day 5/6 (group 2) was performed before stimulation. Oocytes and embryos were cultured in sequential media in 5.5% CO(2), 5% O(2), 89.5% N(2) and 90% humidity. A maximum of two embryos was transferred. RESULTS: The two groups were similar for age, IVF indication, number of treatment cycles, rate of ICSI/IVF, number of fertilized oocytes and number of embryos transferred. The CPR/oocyte retrieval was comparable in group 1 (32%) and in group 2 (44%), while the CPR/embryo transfer was significantly higher (P < 0.01) in group 2 (60%) than in group 1 (35%). Similarly, the implantation rate per embryo transferred was significantly higher (P < 0.03) in group 2 (46%) than in group 1 (29%). The cryo-augmented delivery rate/oocyte retrieval was comparable in group 2 (36.3%) and in group 1 (28.6%). CONCLUSION: This randomized study in an unselected population showed a significantly higher CPR/embryo transfer and a tendency toward a higher CPR/oocyte retrieval in patients receiving blastocysts when compared with day 2 transfers.