Pregnancy Pillows: Do You Need One, and Which Shape Works Best?
Somewhere in the second trimester, sleep usually gets harder. Your bump changes how you can lie, your back and hips start to ache, and the positions you've slept in for years stop working. Later in pregnancy there's also specific guidance on how to sleep. A pregnancy pillow is the simplest tool for both.
This guide covers what the guidance actually says, the main pillow shapes, and how to choose. It isn't medical advice — your midwife or doctor is the right person for anything specific to you.
What the advice says about sleeping position
UK maternity guidance is clear on one point. From the third trimester (around 28 weeks), it's safer to go to sleep on your side rather than on your back. Research summarised by the Royal College of Midwives found that going to sleep on your back in later pregnancy is linked to a higher risk of stillbirth (Royal College of Midwives, 2019).
The pregnancy charity Tommy's, which runs the Sleep On Side campaign, adds some practical points (Tommy's):
- Either side is fine. The research didn't find a difference between left and right.
- It applies to every time you go to sleep — at night, after waking in the night, and daytime naps.
- Don't panic if you wake up on your back. Just roll back onto your side.
- Pillows help. Tommy's suggests putting a pillow behind your back to encourage side sleeping.
That last point is where a pregnancy pillow earns its place. It's much easier to stay on your side when there's something behind you stopping you from rolling back.
What a pregnancy pillow does
A good pregnancy pillow does three jobs at once:
- Supports the bump so it isn't pulling on your back and hips.
- Supports your top knee so your pelvis stays level, which is where much of the hip and lower-back ache comes from.
- Sits behind your back so rolling onto it is less likely.
Ordinary pillows can do some of this if you build a fort out of three or four of them. The trouble is they move. A shaped pregnancy pillow keeps everything in place through the night.
The main shapes
| Shape | What it supports | Best for | Drawbacks |
|---|---|---|---|
| Wedge | Bump or back, one at a time | Small beds, travel, earlier pregnancy, tight budgets | Doesn't support the knees; one job only |
| Straight (I-shape) | Bump, top arm and knee | People who like hugging something | Nothing behind you |
| C-shape | Head, bump and knees, or back | Side sleepers with smaller beds | You reposition it when you turn over |
| U-shape | Head, bump, knees and back together | Later pregnancy, people who turn in the night | Takes the most bed space; can feel warm |
Why many people end up with a U-shape
In the third trimester, turning over gets slow and awkward. With most pillows, you turn and then rebuild the support on the other side. A U-shaped pillow has support on both sides already: one side for the bump and knees, the other along your back. You turn inside it rather than taking the pillow with you.
The back support also does the job Tommy's describes — something behind you making it harder to roll onto your back while you're asleep.
The honest downsides are size and heat. A U-shape is about 70cm wide and takes up a real share of a double bed, which matters if you share it. And being surrounded on both sides is warmer, which some people notice more in pregnancy.
When should you start using one?
Whenever you start losing sleep to discomfort. For many people that's somewhere in the second trimester, when the bump begins to change how you lie. The side-sleeping guidance applies from around 28 weeks, so if you haven't got one by then, that's a good time.
Our U-shaped pillow
The Cuddly Pillow™ ($99) is a U-shaped pillow, 140cm × 70cm (55" × 27.5"), with around 7 lbs of fill and a 100% cotton cover that comes off and goes in the washing machine. It's rated 4.6 stars across more than 700 reviews. It isn't designed only for pregnancy, which helps after the baby arrives too — plenty of people keep using it as an everyday side-sleeping pillow.
Before you buy, check your bed: it's comfortable on a double and generous on a queen or larger. If you're short on space or only need bump support, a simple wedge is cheaper and smaller. We don't make one, and for some people it's the better choice.
Frequently asked questions
Do I really need a pregnancy pillow?
No — you can follow the side-sleeping advice with ordinary pillows behind your back and between your knees. A pregnancy pillow just makes it easier, because it stays in place through the night.
Which side should I sleep on when pregnant?
According to Tommy's, either side is fine. The research behind the guidance didn't find a difference between left and right. What matters is going to sleep on your side rather than your back from the third trimester.
What if I wake up on my back?
Don't worry. The advice is to roll back onto your side and go back to sleep. A pillow behind your back makes it less likely to happen.
Is a U-shaped or C-shaped pregnancy pillow better?
A U-shape supports both sides at once, so you don't have to move the pillow when you turn over, but it takes more room. A C-shape is more compact and suits smaller beds. Our comparison of pillow shapes goes into more detail.
Can I use a pregnancy pillow after the baby is born?
Yes, for you. A U-shaped pillow works as an everyday side-sleeping and reading pillow. One important safety point: keep pregnancy and body pillows out of the baby's cot or sleep space. Babies should sleep on a firm, flat surface with nothing loose around them.
Will it fit in a bed with my partner?
On a queen or larger, usually. On a standard double, a U-shape is tight, so a C-shape or wedge may be the friendlier option.
The short version
From around 28 weeks, go to sleep on your side, on either side, and put something behind your back to help you stay there. A pregnancy pillow is the easiest way to do that. Pick a U-shape if you have the bed space and turn in the night, a C-shape if space is tight, and a wedge if you only need a little bump support. For anything specific to your pregnancy, ask your midwife.