Lack of sleep is linked to many health issues, including diabetes, memory loss, hypertension and obesity. Even so, pregnant women may be tempted to do as much snoozing as possible before baby arrives and sleep becomes a distant memory.

But a recent study by the Society for Maternal-Fetal Medicine found that that getting too much or too little sleep can lead to excess weight gain for expectant mothers.

The study monitored the sleep habits of more than 700 pregnant women for seven days and found that two-thirds of the women slept between seven and nine hours a night. Sleeping too much or too little was associated with extra weight gain during pregnancy.

It’s normal to put on 11 to 40 pounds during a pregnancy, depending on your body mass index and other factors such as whether you’re having twins. Talk to your doctor to determine how much weight you can safely gain. If you gain too many pounds, your baby runs the risk of being overweight or having high blood pressure.

As for sleeping during pregnancy, bearing a large bump can make certain sleeping positions uncomfortable. Try pillows, too. To sleep easier, try resting on your side with your legs bent to ease heartburn and backaches and regulate circulation. Stop drinking liquids two to three hours before bedtime to give your bladder a break, and try stretching or deep breathing to calm your mind. The classic bedtime drink, a cup of warm milk, can also aid deep slumber. The National Sleep Foundation recommends sleeping on your left side to improve the flow of blood and nutrients to the fetus, the uterus and kidneys.

With a little awareness, moms-to-be can get the proper amount of rest — and perhaps ward off some extra pounds.