To elucidate a possible role for FGF9 (fibroblast growth factor9) in these events, porcine preimplantation stage embryos were characterized for the presence of FGF9 gene and protein. The objective of this study were to investigate the effects of FGF9 on hormone-stimulated porcine preimplantation stage embryos. Each embryos were collected from non-synchronized (Control; n=5) and after synchronized AI (regumate, PMSG/ hCG; n=5) sows and qPCR analyzed for FGF9 mRNA levels. The synchronization AI embryos had higher (p<0.05) FGF9 mRNA levels than that non-treated group embryos. At these stages of preimplantation development were also analyzed for immunoreactive FGF9 expression. Synchronization AI embryos were strong expression of FGF9. In contrast, non-treated embryos were remained constant during development stage. These results demonstrate the temporal variation of FGF9 mRNA abundance in hormonal stimulation and of immunoreactive FGF9 with the developmental processes occurring in the preimplantation development.