Most pregnant women should aim for 7 to 9 hours of sleep per night, the same range recommended for all adults. There is no separate, pregnancy-specific guideline for sleep duration. But hitting that target becomes both more important and more difficult during pregnancy, since poor sleep is linked to complications like preeclampsia, gestational diabetes, and low birth weight.
Why the 7-to-9-Hour Window Matters More During Pregnancy
Sleep deprivation raises the risk of several serious pregnancy complications, including high blood pressure disorders, gestational diabetes, maternal depression, preterm birth, stillbirth, and low birth weight. Your body is doing significantly more repair and growth work than usual, and sleep is when much of that happens.
The connection between short sleep and gestational diabetes is especially well documented. A large multiracial study published in the American Journal of Obstetrics and Gynecology found that non-obese women who slept only 5 to 6 hours per night had roughly 2.5 times the risk of developing gestational diabetes compared to women who slept 8 to 9 hours. Even sleeping 7 hours doubled the risk. Interestingly, napping seemed to help offset some of that danger: the elevated risk was strongest among women who rarely or never napped.
Poor sleep quality, not just short duration, also plays a role. Research in the Journal of Obstetrics, Gynecology and Cancer Research tied poor sleep quality to higher rates of preeclampsia, preterm delivery, and lower birth weight. So sleeping 8 hours of fragmented, restless sleep may not protect you the same way 8 hours of solid sleep would.
What Makes Sleep So Difficult During Pregnancy
Knowing you need 7 to 9 hours and actually getting them are two very different things. Pregnancy introduces a cascade of sleep disruptors that tend to worsen as the trimesters progress.
In the first trimester, surging progesterone causes intense daytime drowsiness while also increasing nighttime urination. Many women feel exhausted during the day yet struggle to stay asleep at night. By the second and third trimesters, a growing belly makes it harder to find a comfortable position, heartburn intensifies when lying flat, and hip or back pain can wake you repeatedly.
Restless legs syndrome is another common culprit. About 1 in 5 pregnant women develops it, a rate far higher than in the general population. The condition causes an uncomfortable urge to move your legs, particularly at night, and can significantly delay falling asleep. Iron and folate deficiency may contribute, so keeping up with your prenatal vitamins can help.
Snoring and obstructive sleep apnea also become more common as pregnancy progresses, driven by weight gain and swelling of the airways. If your partner notices loud snoring or pauses in your breathing, it is worth bringing up at your next prenatal visit, since untreated sleep apnea during pregnancy is associated with blood pressure problems and reduced oxygen delivery to the fetus.
Best Sleep Positions After the First Trimester
During the second and third trimesters, the American College of Obstetricians and Gynecologists recommends sleeping on your side. Lying flat on your back can compress a major blood vessel that carries blood to your uterus, potentially reducing blood flow to the fetus and making you feel dizzy or lightheaded.
Left-side sleeping is often suggested because it keeps pressure off the liver and may optimize blood flow, but either side is fine. A pillow between your knees and another supporting your belly can reduce hip pain and help you stay on your side through the night. If you wake up on your back, don’t panic. Simply roll to your side and fall back asleep. Brief episodes of back sleeping are not harmful.
Practical Ways to Improve Sleep Quality
Sleep hygiene basics become especially important during pregnancy. Going to bed and waking up at roughly the same time each day helps regulate your body’s internal clock. Keeping your bedroom cool, dark, and quiet removes easy obstacles. Limiting fluids in the hour or two before bed can reduce overnight bathroom trips, though you should still stay well hydrated during the day.
Naps deserve a special mention. The gestational diabetes research found that women who napped regularly had lower risk than those who didn’t, suggesting that making up lost nighttime sleep during the day offers real benefit. A short nap of 20 to 30 minutes in the early afternoon is ideal. Napping too late or too long can make it harder to fall asleep at night.
For heartburn, eating your last meal at least two to three hours before bedtime and propping your upper body slightly with an extra pillow can make a noticeable difference. For restless legs, gentle stretching or a warm bath before bed may ease symptoms.
Sleep Aids That Are Considered Safe
If sleep hygiene changes aren’t enough, certain over-the-counter antihistamines are considered acceptable during pregnancy. Doxylamine and diphenhydramine (the active ingredient in many common sleep aids) can be used without an increased risk of miscarriage, major birth defects, preterm birth, or low birth weight. These are first-generation antihistamines that cause drowsiness as a side effect, which is what makes them useful for sleep.
Melatonin is a different story. It crosses the placenta easily, and there are not enough human studies to confirm its safety during pregnancy. Most clinical guidelines recommend antihistamines over melatonin for pregnant women who need a sleep aid.
Any sleep aid should be used on an as-needed basis rather than nightly, and it’s worth discussing with your provider if you find yourself relying on one regularly, since that may signal a treatable underlying issue like sleep apnea or anxiety.
Too Much Sleep Can Be a Concern Too
While most of the focus is on getting enough sleep, consistently sleeping well beyond 9 or 10 hours may also signal a problem. Excessive sleep in pregnancy has been associated with gestational diabetes risk in some studies, and it can be a sign of depression, thyroid issues, or severe fatigue from anemia. If you’re sleeping 10 or more hours and still feeling exhausted, that pattern is worth mentioning at a prenatal appointment. The goal is consistent, restorative sleep in the 7-to-9-hour range, supplemented by a short nap if needed.