*Implantation is critical to the survival of the embryo; the embryo must adhere and embed itself in the endometrium in order to exchange waste and nutrients. For this reason, the first differentiation of cells is into trophoblasts and syncytiotrophoblasts and the inner cell mass (ICM). | *Implantation is critical to the survival of the embryo; the embryo must adhere and embed itself in the endometrium in order to exchange waste and nutrients. For this reason, the first differentiation of cells is into trophoblasts and syncytiotrophoblasts and the inner cell mass (ICM). |