Molecular signaling in uterine receptivity for implantation

Successful implantation is the result of an. intimate 'cross-talk' between the blastocyst and uterus in a temporal and cell-specific manner: Thus, bot h the uterine and embryonic events must be examined to better understand th is process. Although various aspects and molecules associated with these ev ents have been explored, a comprehensive understanding of the implantation process is still very limited. In this review we have highlighted the impor tance of the blastocyst's activity state and the receptive state of the ute rus in determining the 'window' of implantation. In this context, we provid e a testable scheme that signifies the important roles of various key molec ules in embryo-uterine interactions during implantation. (C) 2000 Academic Press.