Best Sleeping Positions When You're Pregnant

Sleep during pregnancy is one of those things that sounds straightforward until the second trimester arrives and suddenly nothing is comfortable. The belly is growing, the hips are shifting, and the position that worked fine last month now requires three pillows and a structural plan.

There's a lot of advice floating around about what's safe and what isn't. Some of it is useful. Some of it causes unnecessary worry. This guide cuts through the noise and covers what Australian women actually need to know about sleeping positions throughout each stage of pregnancy.

 

Side Sleeping: Left vs. Right

Side sleeping is the position most healthcare providers recommend during pregnancy, and the reason comes down to circulation.

As the baby gets bigger, there's a greater chance the uterus will press against the inferior vena cava - a major vein that runs along the right side of your spine and carries blood back to your heart. If you lie flat on your back, your uterus can squeeze this vein, which is why doctors usually recommend switching to your side for sleep around week 28.

A 2019 review dug into this topic. It found that sleeping on your back does raise some risk during the third trimester. But, honestly, there's no real difference when it comes to sleeping on your left side or your right - both seem just as safe. The catch is, third-trimester pregnancy loss isn't common, so most studies are pretty small. Still, side sleeping is the advice most experts lean toward because it's safer and usually more comfortable, too.

 

Left Side

There's a reason people often suggest the left side. Sleeping on your left helps blood flow better through the inferior vena cava, since the vein sits on your right. Plus, it keeps pressure off your liver and kidneys, so they work more easily.

For women experiencing swelling in the hands, ankles, or feet, this position may support better fluid management overnight.

 

Right Side

Sleeping on the right side is also considered safe. The 2019 review mentioned above found comparable outcomes between left and right side sleeping. There may be a slight risk of IVC compression when lying on the right, but for most women it comes down to comfort and whichever side allows for a better night's rest.

If you wake up having rolled onto the right side, there's no need to panic. Simply shift back when you notice and carry on.

 

Ways to Make Side Sleeping Work

Side sleeping sounds simple until you're actually trying to maintain it for seven or eight hours straight. A few practical adjustments make a significant difference depending on where you are in the pregnancy.

 

First Trimester

In early pregnancy, almost any position is generally fine. If you want to build the habit of side sleeping before it becomes necessary, placing a pillow between your knees is an easy starting point. This small adjustment helps take the load off the hips and reduces lower body discomfort. A memory foam knee pillow can make this even more effective if you find a standard pillow doesn't stay in place through the night.

 

Second Trimester

As the belly starts to grow, mattress firmness becomes more relevant. A mattress that's too soft may allow the back to sag, which creates its own discomfort. If your mattress is on the softer side, placing a firm board underneath can help.

This is also the trimester where a pregnancy pillow starts to earn its place. U-shaped and C-shaped designs wrap around the whole body, supporting the belly from the front and the back simultaneously - which is something a standard pillow simply can't replicate. The Pain Free Aussies Pregnancy Pillow uses a U-shaped design at 140cm x 80cm, wrapping around both sides to support the back, belly, hips, and legs at once. Place the pillow between the legs for hip support, tuck it under the belly, and let the back section do the work of keeping you from rolling.

 

Third Trimester

Continue with the pregnancy pillow as the belly grows larger. Some women find full U-shaped pillows cumbersome in the final weeks. In that case, a wedge pillow tucked under the belly and another positioned behind the back works equally well for maintaining side position without the bulk.

If side sleeping simply isn't happening and you find yourself on your back, try propping the upper body at roughly a 45-degree angle using pillows. This avoids being completely flat and may reduce the compression risk while still allowing rest. Alternatively, elevating the head of the bed slightly with books or blocks under the legs of the bed frame achieves a similar effect.

 

Back Sleeping

Back sleeping is generally considered safe throughout the first trimester. After that, concerns arise as the uterus grows large enough to compress blood vessels when lying flat.

Some studies have linked sleeping on the back to increased stillbirth risk after 28 weeks, though the research is limited and other factors like sleep apnoea may contribute. One analysis suggested that avoiding back sleep after 28 weeks may reduce risk by around 5.8 per cent. Taken in context, that figure represents a small but meaningful consideration worth discussing with your GP. link

Beyond circulation concerns, back sleeping in later pregnancy may also contribute to lower back discomfort, digestive issues, haemorrhoids, and a feeling of lightheadedness. If you wake up on your back, simply roll to the side and settle back in - there's no need for alarm.

The general guideline from Australian midwives and obstetricians is to aim for side sleeping from around 28 weeks, and to discuss your individual circumstances with your healthcare provider if you have specific concerns.

 

The Takeaway

Sleep position is one more thing pregnancy adds to the list, but it doesn't need to become a source of significant stress.

Side sleeping - left or right - is the position most recommended for supporting blood flow as the pregnancy progresses. Getting comfortable in that position is where the practical effort goes, and the right support makes it considerably easier than trying to maintain it through willpower and a couple of inadequate pillows.

A good pregnancy pillow does the structural work for you. The Pain Free Aussies Pregnancy Pillow supports the back, belly, hips, and legs simultaneously, keeps you from rolling through the night, and transitions into a breastfeeding support pillow once the baby arrives. Free shipping across Australia. 30-day money-back assurance.

Prioritise good sleep now. Talk to your GP or midwife about any concerns specific to your pregnancy.

This information is general in nature and not a substitute for professional medical advice. Always consult your GP, midwife, or obstetrician regarding sleeping positions and any other aspects of your health during pregnancy.