Embryo-uterine cross-talk during implantation: the role of Wnt signaling

During mammalian pregnancy, it has been demonstrated that the quality of embryo implantation determines the quality of ongoing pregnancy and fetal development. Recent studies have provided increasing evidence that differential Wnt signaling plays diverse roles in multiple peri-implantation events. This review focuses on recent progress on various aspects of Wnt signaling in preimplantation embryo development, blastocyst activation for implantation and uterine decidualization. Future studies with conditional deletion of Wnt family members are hoped to provide deeper insight on the pathophysiological significance of Wnt proteins on early pregnancy events.