Doctors generally recommend sleeping on your side during pregnancy, especially as time goes on. Sleeping on your left side is often referred to as the “ideal” scenario during pregnancy because it allows for optimal blood flow from the inferior vena cava (IVC), which carries blood to your heart and, in turn, to your baby. However, sleeping on your right side is also perfectly acceptable. Sleeping on your back in late pregnancy is not recommended because it can cause lower oxygen levels in the baby due to compression of blood vessels supplying the uterus. Therefore, it is best to avoid sleeping on your back after the first trimester. While there is no conclusive evidence that sleeping on your left side reduces the risk of stillbirth, some studies have suggested that it may be beneficial. If you have trouble sleeping on your side, you can try using pillows to prop your upper body at a 45-degree angle or elevating the head of your bed a couple of inches with books or blocks.