In late pregnancy, you don’t have to sleep on your left side, you can also sleep on your right side. In the middle and late stages of pregnancy, the enlarged uterus compresses the abdominal aorta and inferior vena cava when lying down, so that the inferior vena cava reflux is blocked, the side lying position or sitting position can lift the uterine compression, improve venous reflux, which is favorable to the uterus and placenta’s blood supply. Some studies have confirmed that, for individual pregnant women, the normal late pregnancy pregnant women position change is conducive to regulating the umbilical artery blood flow rate, in the direction of favorable to the fetal blood circulation and oxygen supply, but also confirmed that the left position and the right position, as well as favorable to the fetal blood supply. Therefore, according to the comfort level of the pregnant woman, she can lie on the left side or the right side. It is recommended to create a good sleeping environment and maintain the right temperature and humidity in the room, which can improve the quality of sleep of pregnant women.