RESUMO
OBJECTIVE: To investigate the impact of early cleavage (EC) on embryo quality, implantation, and live-birth rates. DESIGN: Prospective cross-sectional study. SETTING: Multicenter study. PATIENT(S): Seven hundred embryo transfers and 1,028 early-stage human embryos. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Implantation according to the presence of EC and embryo quality. RESULT(S): The presence of EC is associated with embryo quality, especially in cycles with autologous oocytes. However, the use of EC as an additional criterion for selecting an embryo for transfer does not appear to significantly improve likelihood of implantation. Furthermore, embryos that presented EC had live-birth rates per implanted embryo similar to those that did not show any sign of cleavage. CONCLUSION(S): At least for conventional embryo culture and morphologic evaluations, the additional evaluation of EC in embryos may not be valuable to improve embryo implantation.
