Abstract

To assess the accuracy of day 3 morphologic criteria in identifying the best embryos.Prospective observational study.University IVF program.One hundred cycles in women desiring blastocyst transfer who had > or =3 eight-cell embryos on day 3.On day 3, the embryologist chose the two embryos that would have been transferred that day. On day 5, embryos were examined to determine the best and second-best blastocysts.Accuracy of day 3 picks as measured in culture on day 5, outcome of nontransferred picks, and cryopreservation rate.All cycles reached the blastocyst stage and 73% had cryopreservation. The mean number of blastocysts was 4.8 (3.2 on day 5 and 1.6 on day 6). Neither pick was chosen in 39% of cycles; one pick was transferred in 38%; and both picks were transferred in 23%. Of 116 nontransferred picks, 51 were frozen and 65 arrested, with both picks arresting in 9 cycles. The single best blastocyst was chosen from the picks in 39% of cycles.Morphologic criteria for cleavage-stage embryo selection may fall short when the transfer is limited to two embryos. Culture to blastocyst is warranted in this population to avoid high-order multiples and still be able to choose the two embryos with the highest implantation potential.

View details for PubMedID 12057727