CCS data of 4cell
Oocytes and embryos were isolated in M2 medium (Sigma) at 20h post-hCG, then while oocytes were lyse directly, the embryos were not lyse until they develop to defined stages: zygotes (24-26h post hCG), two-cell stage (46-48h post-hCG), four-cell stage (54-58h post-hCG), eight-cell stage (68-70h post-hCG), blastocyst stage (94-96h post-hCG), with culturing in KSOM media (Merck Millipore) at 37 with 5% CO2.