You asked

Can I sleep on my back in late pregnancy?

Around half way through your pregnancy you should stop attempting to sleep on either your stomach or your back. Not only will these positions be uncomfortable, but they may also have negative physical effects on you and your unborn child.
When sleeping on your back the pressure on the uterus can cause your blood veins to limit the amount of blood being delivered to yoru heart. This in turn causes a decrease in blood to your baby. This could cause you to feel sick or dizzy and is not good for either you or your baby. This type of sleeping position has been known to slow down the heartbeat of a baby as well, due to the lack of circulation. If you have high blood pressure problems, it is even more imperative that you sleep on your side. To promote the best circulation it is recommended that you sleep on your left side.
However, we all shift in our sleep so do not worry if you wake up on your back. However, to keep the blood and nutrients your baby needs flowing to the placenta and uterus, try propping yourself up to avoid accidentally moving into a back sleeping position.

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