Sleeping position in pregnancy: which way is best?

Sleep gets harder as your bump grows. Here’s the advice on which way to sleep, why it matters in the third trimester, and how to get comfortable.

The advice

Tommy’s says the advice for pregnant women is to go to sleep on their side for any episode of sleep in the third trimester. That includes sleep at night, going back to sleep after waking up, and daytime naps.

Why side-sleeping?

You don’t need to worry if you wake on your back: just roll onto your side. The advice follows research called the MiNESS study. Tommy’s says the risk of stillbirth is doubled if women go to sleep on their backs in the third trimester, and that this has been found consistently across four studies in different countries. Tommy’s says the study estimated about 3.7% fewer stillbirths, roughly 130 babies a year, if every pregnant woman in the UK slept on her side in the third trimester. Tommy’s also says the study did not find a difference between sleeping on your left or right side, so either side is fine. Stillbirth is rare, and a doubled risk of a rare event is still a small risk. Side-sleeping is a simple step that helps.

What if I wake up on my back?

Tommy’s says you should not be concerned if you wake up on your back. Simply roll back on to your side. What matters is the position you go to sleep in.

Tips for staying on your side

Put a pillow or two behind your back so you stay tipped to one side.
Put a pillow between your knees and under your bump for comfort.
A long body pillow can support your back, tummy and legs together.
If you get hip pain, try switching sides during the night.

What about earlier in pregnancy?

The Tommy’s advice is for the third trimester. If you’re not sure whether it applies to you yet, ask your midwife.

If you can’t sleep

Sleep problems in pregnancy are common. Heartburn, needing the toilet, aches and a busy mind all play a part. Remember that caffeine counts towards your daily limit: see caffeine in pregnancy. If you’re feeling low or anxious as well as tired, mention it to your midwife, and see loneliness and low mood in pregnancy.

When to get help

If your baby’s movements slow down, stop or change, don’t put it down to the way you slept. Call your midwife or maternity unit straight away, and don’t wait until the next day. For anything else that worries you, such as severe pain, bleeding or feeling very unwell, contact your midwife, maternity unit or NHS 111.

Questions people ask

Does this apply before the third trimester?

The Tommy’s advice is for the third trimester. Ask your midwife if you’re unsure about earlier on.

Which side is better, left or right?

Tommy’s says the study did not find a difference in risk between the left and right side.

What if I always wake up on my back?

Don’t worry. Roll onto your side and go back to sleep. Pillows behind your back can help.

Does this apply to naps?

Yes. Tommy’s says the advice is for any episode of sleep in the third trimester, including daytime naps.