Trophoblastic Wave

Trophoblasts are unique cells of the blastocyst (in the developing embryo) that form the placenta's major part. These trophoblastic cells must invade the uterine lining to provide sufficient anchorage to the developing fetus. The invasion of the trophoblast into the maternal spiral arteries is vital to ensure adequate fetal nutrient and oxygen supply. This process is called endovascular trophoblast invasion, and it occurs in two waves; the first wave is an invasion into the decidual segments of the spiral arteries, and the second wave is an invasion into the myometrial segments.