1. A major blood vessel known as the inferior vena cava runs up your back from your legs. It is responsible for returning blood to your heart. As your uterus and your belly grow, there is increased pressure on this vessel when you are lying flat on your back. You know that you’ve been in this position too long if you have the sensation that your legs are falling asleep or you just feel uncomfortable. As your pregnancy progresses, you will probably be more comfortable lying on your side. This position allows maximum blood flow through your body and to your placenta and baby.

    We all move around a great deal while we are sleeping. Please don’t worry if you wake up on your back; this is perfectly normal. Just reposition yourself so that you are comfortable.

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Ask Tori!

Ask Tori RN®, by registered nurse and resident author of The Joy of Pregnancy, is a helpful and reassuring resource for parents-to-be.