Pregnant women like to sleep on the right side, choose the right side of the bed to rest can be, pregnant women can choose their own comfortable position during pregnancy sleeping position. In the middle and late pregnancy checkups, doctors should instruct pregnant women to lie on their left side because in the middle and late pregnancy, the uterus will rotate to the right, and the inferior vena cava is located on the right side of the abdomen, so the right-rotated uterus will easily compress the inferior vena cava, resulting in supine hypotension syndrome, which manifests as dizziness, nausea, vomiting, chest tightness, cold sweat, rapid heartbeat, decreased blood pressure and other uncomfortable symptoms. Not all pregnant women will have this supine hypotension syndrome, and they can sleep in their own comfortable position during pregnancy.