Romper: Pregnancy’s shifting hormones and physical changes are a recipe for bad sleep.

The American College of Obstetricians and Gynecologists (ACOG) defines insomnia as “Being unable to get enough sleep to feel refreshed, for at least three nights a week for one month or longer.” The organization noted that insomnia happens when a person is trying to sleep and has enough time to sleep, but cannot.

“Insomnia is extremely common during pregnancy, affecting more than half of pregnant women, particularly in the third trimester as your body undergoes physiological changes and your belly is rapidly growing,” Paul Osterdahl, D.O., an obstetrician with Inspira Medical Group, tells Romper.

Though there are no exact figures available for exactly how many expectant parents experience insomnia, Lyon estimates that upwards of 75% of women may experience insomnia at some point during pregnancy.

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