How to Sleep on Your Side During Pregnancy (And What to Do If You Wake Up on Your Back)

Q: Is it okay to sleep on my right side during pregnancy?

Yes. Either side is fine. The guidance to sleep on your side applies to both left and right. Sleep on whichever side is more comfortable for you.

Q: What happens if I wake up on my back while pregnant?

Simply roll back onto your side and go back to sleep. NSW Health guidance is clear that the concern is about falling asleep on your back in the third trimester, not rolling there during the night. Your body will generally alert you if circulation is being significantly affected. Try not to let it become a source of anxiety.

Q: When should I start sleeping on my side during pregnancy?

The formal guidance from NSW Health applies from 28 weeks, but many women start practising earlier because side sleeping with a growing bump becomes more comfortable with support anyway. Starting earlier means your body adapts before the stakes are higher.

Q: Can a pregnancy pillow stop me from rolling onto my back?

A pillow or wedge placed behind your lower back makes rolling less likely by giving you something to lean against. It won't physically prevent movement, but combined with a comfortable side-sleeping setup, most women find they roll back far less often.

Q: Is back sleeping dangerous in the first trimester?

No. The guidance applies from 28 weeks because this is when the uterus becomes large enough that lying flat can affect blood flow. In the first and early second trimester, sleep in whatever position is comfortable.

NSW Health guidance is clear: sleep on your side from 28 weeks. But nobody tells you what to do when you keep waking up on your back at 2am. Here's the full picture.

Sleep March 16, 2026 5 min read

Pregnant woman lying on her side in bed with a pillow supporting her bump for comfortable sleep

In this article

"I keep waking up on my back at 2am and I panic every single time."

If that's you, this post is for you. You're not alone, and you're not doing anything wrong. Side sleeping during pregnancy is genuinely important, but the advice most people receive is incomplete. You're told what to do without being told why, how, or what to do when it doesn't go to plan.

This post covers all of it.

Why side sleeping matters from 28 weeks

From around 28 weeks, healthcare guidance in Australia and the UK consistently recommends starting sleep on your side rather than your back. This is based on research suggesting that going to sleep on your back in the third trimester is associated with a small but measurable increased risk of stillbirth.

The key phrase there is "going to sleep." The concern is about the position you fall asleep in, not the position you wake up in.

Left or right side? Either is fine. You may have heard that the left side is better for circulation, and while there is some evidence for this, the guidance from organisations including Tommy's and the Lullaby Trust is that either side is acceptable. Don't stress about which side. Just pick the one that's comfortable.

Why so many people struggle to actually do it

Knowing you should sleep on your side and being able to sleep on your side comfortably are two different things.

Here's what gets in the way:

You're a natural back sleeper. If you've slept on your back your whole life, side sleeping can feel foreign. Your body knows how to relax in one position, and being told to lie differently doesn't automatically make it comfortable.
Hip pain kicks in. When you lie on your side without adequate support, your top hip drops forward, pulling on your lower back and putting uneven pressure on your hips. This is incredibly common from the second trimester onwards and gets worse as your bump grows.
The bump creates pressure. Without support underneath, the weight of your growing bump pulls down when you lie on your side, creating tension across your lower back and hips.
Reflux. Many pregnant women experience heartburn that lying flat makes worse. Sleeping slightly propped can help, but that can conflict with side lying positions.

None of this means side sleeping isn't possible. It means you need a bit of setup to make it work.

How to actually make side sleeping comfortable

The goal is to keep your spine neutral, your hips stacked, and your bump supported. Here's how to build that:

Pillow between your knees. This is the single most effective adjustment you can make. A pillow between your knees stops your top hip from rolling forward, which reduces the hip and pelvic pain that makes side sleeping hard to maintain. It needs to be thick enough to keep your knees roughly hip-width apart.
Support under your bump. As your bump grows, a wedge or small pillow tucked underneath provides lift that prevents that downward pull. Even in the second trimester, this makes a noticeable difference.
Something behind your back. Placing a pillow or wedge behind your lower back does two things: it gives you something to lean against slightly, which is more comfortable than lying unsupported in open air, and it discourages you from rolling onto your back without feeling trapped.
A slightly elevated head position. If reflux is an issue, try raising the head of your bed a few centimetres or sleeping on an extra pillow. This uses gravity to keep stomach acid down without affecting your side-lying position.

The challenge with this setup using regular pillows is that they shift during the night. You roll, the pillow moves, the alignment is gone, and you're awake at 3am rearranging bedding.

What to do if you wake up on your back

Take a breath. Then roll back onto your side.

That's it.

NSW Health's guidance is clear on this: if you wake up on your back, don't panic. Simply roll back onto your side and go back to sleep. Simply roll back onto your side and go back to sleep. Your body will generally alert you if blood flow is significantly restricted. The research concern is about falling asleep on your back repeatedly, not about accidentally rolling there during the night.

Anxiety about this is completely understandable. Sleep anxiety in pregnancy is real and common. But waking up on your back once (or every night) is not a reason to lie awake in fear. Acknowledge it, roll over, and rest.

If you find you're consistently waking on your back and this is distressing you, speak with your midwife. They can reassure you based on your specific pregnancy and help you figure out whether additional support would help.

When a proper support system makes a difference

For some people, a bit of repositioning is enough. For others, especially from the third trimester or with hip and pelvic pain, a more structured system makes side sleeping genuinely sustainable rather than a nightly battle.

The Bumpnest Maternity Pillow is designed specifically around this. Rather than one large body pillow, it uses a modular system that supports three zones separately: under the bump, between the knees, and behind the lower back. Because each component is positioned where you actually need it, it stays put better than a single pillow and takes up less of the bed.

It's not a medical device and it won't prevent you from rolling. What it does is make the recommended position comfortable enough that your body actually wants to stay there.

If you're already in pain, already losing sleep, or heading into the third trimester and want to get ahead of it, it's worth a look. There's a 50-night trial so you can test it properly.