The left side sleeping position is mainly adopted in late pregnancy mainly because of the following points: 1. The left side sleeping position of pregnant women is conducive to improving the phenomenon of right rotation of the uterus, which can improve the tension of the uterine vessels and can ensure the blood flow of the placenta and avoid the phenomenon of fetal hypoxia and ischemia in the uterine cavity, which is more beneficial to the growth and development of the fetus. 2. The left side sleeping position can avoid The left side sleeping position generally does not cause fetal hypoxia, and the fetus can maintain normal fetal movement. As the left side sleeping position has more benefits to the pregnant woman and the fetus, so in the late pregnancy should try to take the left side sleeping position. However, if the left side sleep position appears to hold gas and chest tightness, you can take your own comfortable position to sleep.