RESUMEN
OBJECTIVE: A variety of studies randomizing women/cycles or oocytes/embryos has been carried out to compare different culture media for culturing embryos up to cleavage or blastocyst stages showing controversial results. A recent systematic review suggested that data in the literature are insufficient to conclude the best culture medium for embryo quality, pregnancy and implantation. The objective of this study was to evaluate whether there is any difference between two commercial culture media regarding clinical outcomes after IMSI cycles. METHODS: A total of 120 patients, ≤39 years of age, undergoing ART treatment submitted to the IMSI program were prospectively broken down and randomized into two groups: Group I (Cook media) and Group II (Vitrolife media). RESULTS: Our data demonstrated that there was no difference using all the media from Cook or all the media from Vitrolife, for culturing embryos till day 2, in the bench incubator at low O2 concentration, in relation to fertilization, embryo quality, pregnancy and implantation rates (p>0.05). CONCLUSION: Both culture media used, Cook medium and Vitrolife medium, for the IMSI procedure and for later embryo culture with transfer on the second day, are equally effective and can be used depending on the ease and availability of acquisition.