The placenta is the organ that anchors the developing fetus to the uterine wall for providing nutrients and waste removal of the fetus. Normal placenta has a single chorionic plate and a fetal decidual portion. Under normal circumstances, it is implanted on the posterior wall in the upper part of the body of the uterus. On implantation of the blastocyst into the endometrium, the outer layer of the blastocyst forms the trophoblast. This trophoblastic layer differentiates into the outer syncytiotrophoblast layer and inner cytotrophoblastic layer. The cytotrophoblast is a cuboidal cell, which forms the syncytiotrophoblast, and the intermediate trophoblast. The syncytiotrophoblast is a multinucleated giant cell structure, which secretes human chorionic gonadotropin (hCG). The intermediate trophoblast anchors the placenta to the decidua and myometrium, replaces the spiral arteries of basal plate and helps establish the foeto-maternal circulation.