As your belly grows, sleeping on your back may not be good for you. It puts the weight of your uterus on your spine and back muscles. In the second and third trimesters, lying on your back may compress a major blood vessel that takes blood to your uterus, making you feel dizzy and possibly reducing blood flow to your fetus.

Sleeping on your side during your second and third trimesters may be best. Keep one or both knees bent. It may help to place a pillow between your knees and another under your belly. You also can try a full-length body pillow for support.

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Published: January 2021

Last reviewed: January 2021