RESUMO
OBJECTIVE: To determine whether altering selected components of sequential culture media can improve early development variables of human embryos. DESIGN: Prospective, randomized, sibling oocyte split trial. SETTING: Private ART center. PATIENT(S): Two hundred eight undergoing treatment with in vitro fertilization or microinjection. INTERVENTION(S): Oocytes from each patient were randomly allocated to fertilization and cleavage media of a control and a trial culture medium formulation. MAIN OUTCOME MEASURE(S): Rates of fertilization, cleavage, and uncontrolled division; average embryo morphology score; blastomeres per embryo; embryo score parameter (number of blastomeres x embryo morphology grade); and embryo utilization. The trial media resulted in a higher fertilization rate, higher cleavage rate, lower rate of uncontrolled division, higher number of blastomeres per embryo, higher average embryo morphology score, a higher embryo score parameter, and higher embryo utilization rate compared to the control media. All differences were statistically significant. CONCLUSION(S): Improved sequential stage-specific culture media can reduce the occurrence of severe human embryo fragmentation and improve developmental variables in early IVF- and ICSI-generated embryos.