. Embryos were
checked for cleavage and developmental status at
approximately 56 hours after vortexing. Noncleaved
oocytes were discarded. Embryos that had only developed
to the two- to five-cell stage were considered retarded
and cultured in a separate well from the more advanced,
normal-appearing embryos with six or more cells. All
embryos were cultured for an additional 4.5 days in CDM-
2 at 38.5 C in 5% CO2, 5% O2, and approximately 90% N2
in humidified air. Embryos in the retarded group only