Sallem A, et al. - Analysts research the possible benefits of extending the culture of poor-quality day-2 embryos (PQE) versus good-quality embryos (GQE) and aim to identify factors related to pregnancy and live birth when transferring frozen-thawed blastocysts originating from GQE and PQE. This study suggests that the PQE are able to reach the blastocyst stage, to implant, and to give healthy babies. Women age and day of blastocyst expansion are predictive of pregnancy and live birth.