Generally speaking, it is better to sleep on the side in late pregnancy, and both the left side and right side positions are acceptable. After pregnancy, with the increase of gestational weeks, the enlarged uterus will compress the inferior vena cava, especially in late pregnancy when pregnant women lie on their backs for a long time, it will be due to the decrease in the volume of return blood and cardiac output, which will lead to low blood pressure, fainting and other symptoms. Therefore, it is not recommended that pregnant women sleep in the supine position in late pregnancy, and it is recommended that they change to the lateral position, both the left side and the right side. Studies have shown 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 side of the lying position and the right side of the lying position, are conducive to the fetal blood supply. With the increase of pregnancy weeks, the burden of pregnant women’s organs and the lumbar spine will increase, the increasing uterus on the pelvic floor tissue compression will become more and more obvious, there will be varicose veins of the lower limbs and vulva, lower limb edema, low back pain, hemorrhoids, constipation and other symptoms. You can give timely treatment under the guidance of your doctor to relieve the discomfort that occurs during pregnancy.