The shape and color of the placenta will vary slightly from one pregnancy to another, but in general, the placenta is usually grayish, translucent and disc-shaped. The placenta is disc-shaped, thick in the center and thin at the edges, with a smooth, translucent off-white color and a central umbilical cord with blood vessels connected by branches to each of the chorionic cotyledons. The placenta is divided into daughter side and mother side, the side toward the amniotic cavity is smooth and called daughter side, the other side is rough and called mother side. The placenta is composed of amnion, lobulated chorionic membrane and fundus mater. The amnion is a translucent membrane attached to the zygote, the lobulated chorionic membrane is the main structure of the placenta, and the fundus mater is the endometrium attached to the maternal part of the uterus. The placenta is an important link for the fetus to obtain nutrition in the mother, and is an organ for material exchange between the mother and the fetus, including gas exchange, nutrient supply and fetal metabolites excretion. The placenta can also synthesize trophoblast cells, which can synthesize a variety of hormones, enzymes, cytokines, etc., and play an important role in maintaining a normal pregnancy. The majority of placentas are spontaneously detached and delivered within half an hour after delivery. After delivery, the placenta should be observed for completeness, and if there is incomplete placenta, follow the doctor’s advice and perform a clearance procedure.