Figure 4From: PreImplantation Factor (PIF) correlates with early mammalian embryo development-bovine and murine modelsPIF levels in atretic embryos are similar to non-cleaving embryos. The medium collected from embryos that failed to progress from day 3 to day 7 of culture were analyzed sequentially and levels Mean+/-SEM were compared with non-cleaving embryos. There were no significant differences among the groups tested (n = 5-15/group).Back to article page