Yes, your body needs more sleep during pregnancy. Most experts recommend at least 7 to 9 hours per night, and many pregnant women find they need closer to the upper end of that range or even more. The reason is straightforward: your body is doing significantly more work than usual, and the hormonal shifts that sustain pregnancy also drive a powerful need for rest.
Why Pregnancy Makes You So Tired
Progesterone is the main driver. This hormone rises sharply in the first trimester to maintain the pregnancy, and it also happens to be strongly sleep-promoting. It triggers daytime drowsiness and earlier sleep onset, which is why many women feel an almost irresistible urge to nap well before they’re visibly pregnant. Another early pregnancy hormone, human chorionic gonadotropin, has a similar sedating effect.
Beyond hormones, your cardiovascular system ramps up quickly. Blood volume increases to supply the developing placenta, which makes your heart pump harder and faster. Your breathing rate rises too. All of this extra metabolic work burns energy, and sleep is when your body recovers from it. The fatigue you feel in early pregnancy isn’t a sign that something is wrong. It’s a signal that your body is redirecting enormous resources toward building a new circulatory system and growing a placenta.
How Sleep Changes Across Trimesters
The first trimester is often the sleepiest. Progesterone levels are climbing rapidly, and many women find they can barely stay awake past 8 p.m. Nausea can also disrupt sleep, but the hormonal drive toward drowsiness is usually the dominant experience.
The second trimester typically brings some relief. Energy levels rebound for many women, and sleep quality often improves compared to the first trimester. Napping remains common, with studies showing pregnant women averaged about 65 minutes of daytime napping during the second trimester.
The third trimester is when sleep gets hardest. Research using overnight sleep monitoring shows that late pregnancy brings shorter total sleep time, more nighttime awakenings, less deep sleep, and less REM sleep compared to earlier in pregnancy. Women spend more time in lighter sleep stages, which means even a full night in bed may not feel restorative. The hormone oxytocin, which triggers uterine contractions, peaks at night and can fragment sleep further in the final weeks.
What Keeps You Awake
The list of physical sleep disruptors grows as pregnancy progresses. Frequent urination is nearly universal and often wakes women multiple times per night. Heartburn worsens as the uterus pushes against the stomach. Back pain and hip pain make it harder to find a comfortable position.
Restless legs syndrome affects 10 to 34% of pregnant women. It causes an uncomfortable crawling or pulling sensation in the legs, usually worse at night, that creates a strong urge to move. For women who develop it, the condition can significantly delay falling asleep and cause repeated nighttime awakenings.
Sleep apnea also becomes more common during pregnancy. Among nonpregnant women of reproductive age, the prevalence is roughly 1 to 6%. In pregnant women, rates range from 8 to 20%, and by the third trimester, one study found the prevalence reached 24%. Weight gain, fluid retention, and even tongue swelling (which increases the odds of sleep apnea roughly sixfold) all contribute. If you’ve started snoring loudly during pregnancy or your partner notices pauses in your breathing, that’s worth mentioning to your provider.
Why Getting Enough Sleep Matters
Poor sleep during pregnancy isn’t just uncomfortable. It carries measurable health risks for both you and your baby. Women who slept fewer than 6 hours per night had a significantly higher risk of developing preeclampsia, a dangerous blood pressure condition. In one study, short sleep was associated with more than 7 times the risk of preeclampsia after adjusting for other factors. Sleeping fewer than 5 hours raised the risk even further.
Sleep also appears to affect fetal growth, particularly in early pregnancy. Women who got 7 hours or less of sleep per day during the first trimester had nearly twice the risk of having a smaller-than-expected baby. When poor sleep quality and short sleep duration occurred together, the risk was about double. This suggests that the first trimester, when many women feel the most exhausted, may be the most important window for prioritizing rest.
Maternal sleep disturbance has also been linked to a higher risk of preterm birth, though the relationship is complex and involves multiple overlapping factors.
Sleep Position After 28 Weeks
Once you reach the third trimester, how you sleep starts to matter in addition to how much you sleep. Research has found that going to sleep on your back is associated with about 2.3 times the risk of late stillbirth compared to falling asleep on your left side. The mechanism is likely pressure from the uterus compressing major blood vessels when you’re flat on your back, which can reduce blood flow to the baby.
The practical takeaway: try to fall asleep on your side, preferably the left. If you wake up on your back, simply roll over. The research measured the position women fell asleep in, not every position they shifted into overnight. A pillow behind your back or between your knees can help you stay on your side more comfortably.
Practical Ways to Get More Rest
Napping is one of the most effective strategies, and there’s no reason to feel guilty about it. Research on pregnant women found that increased daytime napping during the second trimester was associated with better outcomes. Naps of 20 to 45 minutes tend to improve alertness without making it harder to fall asleep at night, though many pregnant women nap longer and still sleep fine.
For nighttime sleep, a few adjustments help most women. Limiting fluids in the hour or two before bed reduces overnight bathroom trips. Sleeping with your upper body slightly elevated can ease heartburn. A pillow between the knees takes pressure off the hips and lower back. Keeping the bedroom cool counteracts the temperature increase that progesterone causes.
If restless legs are keeping you awake, iron and folate levels are worth checking, since deficiencies in both are common during pregnancy and linked to restless legs. Gentle stretching or a warm bath before bed can also reduce symptoms. For persistent sleep problems, especially loud snoring or gasping during sleep, a conversation with your provider can identify whether a sleep disorder needs attention.