Sleeping on Right vs Left Side During Pregnancy: Which Is Better?

Quick take: Sleeping on your left side is the position most often recommended by doctors during pregnancy—especially after 24 weeks—because it supports the best blood flow to your baby and helps reduce swelling and heartburn. That said, sleeping on your right side is still considered safe for most women, though it may slightly reduce circulation compared to the left. The key is comfort and avoiding your back after the first trimester. If you wake up on your right or back, don’t panic—just roll back to your side and use pillows for support. Always talk to your provider if you have concerns about sleep position and your baby’s well-being.

You’re 28 weeks pregnant, staring at the ceiling at 3 a.m., every pillow in the house wedged around you like a makeshift fort. You’ve read the advice—“sleep on your left side!”—but no one told you how to actually stay there. You roll to your right, and suddenly your mind races: Is this safe? Am I cutting off blood flow? What if I roll onto my back? You’re not alone. Nearly every pregnant woman has lain awake, heart pounding, wondering if her sleep position is harming her baby.

Here’s the truth: while sleeping on your left side is ideal for circulation and comfort, sleeping on your right side is still safe for most women. What matters most is avoiding your back after the first trimester and finding a position that lets you rest. In this complete 2026 guide, we’ll break down the science behind left vs. right side sleeping, how it affects your baby, and practical tips to stay comfortable all night. No guilt, no fear—just clear answers and a plan for better sleep.

Is It Safe to Sleep on the Right Side During Pregnancy?

Yes, it’s generally safe to sleep on your right side during pregnancy. While doctors often recommend the left side for optimal blood flow, sleeping on your right is not considered dangerous for most women. The concern stems from the anatomy of your major blood vessels: the inferior vena cava (IVC), which carries blood from your lower body back to your heart, runs along the right side of your spine. When you lie on your right side, the weight of your uterus can slightly compress this vein, potentially reducing blood flow to your baby and causing dizziness or low blood pressure in some women.

However, the compression is usually minimal, and your body is designed to adapt. A 2022 study published in Obstetrics & Gynecology found no significant increase in adverse pregnancy outcomes for women who slept on their right side compared to their left. The key takeaway? If you wake up on your right side, don’t stress—just roll back to your left if you can. The bigger concern is sleeping on your back, which we’ll cover later.

That said, if you have certain high-risk conditions—such as preeclampsia, intrauterine growth restriction (IUGR), or a history of placental issues—your provider may advise you to prioritize the left side. Always check with your OB/GYN or midwife if you’re unsure, especially if you experience dizziness, shortness of breath, or notice reduced fetal movement when lying on your right.

Benefits of Sleeping on the Left Side for Pregnant Women

• Improves blood flow to the placenta and baby. The left side position helps keep the IVC (the large vein on your right side) uncompressed, allowing for better circulation. This means more oxygen and nutrients reach your baby, which is especially important in the second and third trimesters when your baby is growing rapidly.
• Reduces swelling in your hands, feet, and ankles. Edema (swelling) is common in pregnancy due to increased fluid retention. Sleeping on your left side helps your kidneys filter waste and excess fluid more efficiently, which can ease puffiness. One reader, Sarah, shared: “I noticed my feet were less swollen in the mornings when I made an effort to sleep on my left side. It was a small change, but it made a big difference.”
• Eases heartburn and acid reflux. As your uterus grows, it can push stomach acid up into your esophagus, causing that burning sensation. Sleeping on your left side helps keep your stomach below your esophagus, reducing the likelihood of reflux. If heartburn is keeping you up at night, this position—along with avoiding spicy or acidic foods before bed—can bring relief.
• Supports kidney function. Your kidneys work overtime during pregnancy to filter waste from both you and your baby. The left side position helps them drain more efficiently, which can reduce the risk of urinary tract infections (UTIs) and kidney stones.
• May lower the risk of stillbirth. A large 2021 study from the International Journal of Epidemiology found that women who slept on their left side in the third trimester had a slightly lower risk of stillbirth compared to those who slept on their back or right side. While the absolute risk remains very low, the findings suggest that left-side sleeping may offer additional protection for your baby’s well-being.

Of course, the left side isn’t always comfortable—especially if you’re used to sleeping on your right or stomach. The good news? You don’t have to stay in one position all night. If you wake up on your right side, it’s okay to stay there. The goal is to start on your left and use pillows to make it easier to stay there longer.

How Does Sleeping Position Affect Fetal Blood Flow?

Your baby’s blood supply depends on a steady flow of oxygen and nutrients through the placenta, which is connected to your uterus. When you lie down, the position of your body can influence how efficiently that blood flows. Here’s how it works:

• Left side: The IVC (the vein that returns blood from your lower body to your heart) is on the right side of your spine. When you lie on your left side, the IVC remains uncompressed, allowing blood to flow freely back to your heart and then to the placenta. This position also helps your uterus avoid pressing on your liver, which is located on the right side of your abdomen.
• Right side: When you lie on your right side, your uterus may slightly compress the IVC, which can reduce blood flow to your heart and, in turn, to your baby. However, the compression is usually minor, and your body compensates by increasing blood flow through other vessels. Most women won’t notice any difference, but if you have a condition like IUGR (where the baby isn’t growing as expected), your provider may recommend prioritizing the left side.
• Back: This is the position to avoid after the first trimester. When you lie flat on your back, the weight of your uterus can compress the IVC and the aorta (the artery that carries oxygen-rich blood from your heart to your body and placenta). This can significantly reduce blood flow to your baby and may cause dizziness, shortness of breath, or even a drop in blood pressure for you. A 2023 study in JAMA Network Open found that women who spent more than 30 minutes on their backs during sleep had a higher risk of stillbirth, though the overall risk remains low.

To visualize this, imagine your circulatory system as a garden hose. When you lie on your left side, the hose (your blood vessels) stays open and water (blood) flows freely. When you lie on your right side, the hose might get slightly kinked, but water still gets through. When you lie on your back, the hose gets completely flattened, and water stops flowing. That’s why avoiding your back is the most important rule.

If you’re worried about blood flow, pay attention to your baby’s movements. Most providers recommend doing a daily “kick count” starting around 28 weeks. If you notice a significant decrease in movement—especially after lying in a certain position—contact your provider. In most cases, a simple position change or a snack will get things moving again.

Can Sleeping on the Left Side Reduce Pregnancy Swelling?

Yes, sleeping on your left side can help reduce swelling (edema) in your hands, feet, and ankles—a common and often uncomfortable symptom of pregnancy. Here’s why it works:

• Gravity helps fluid drain. When you lie on your left side, gravity assists your lymphatic system in draining excess fluid from your tissues. This is especially helpful for swelling in your lower body, like your feet and ankles.
• Your kidneys work more efficiently. The left side position helps your kidneys filter waste and excess fluid from your bloodstream more effectively. This can reduce water retention and ease puffiness.
• Less pressure on your veins. Your uterus can press on the veins in your pelvis when you lie on your back or right side, slowing blood flow and contributing to swelling. The left side position helps relieve this pressure.

One reader, Maria, shared her experience: “I struggled with swollen feet so bad that I couldn’t wear my regular shoes by the end of the day. My midwife suggested sleeping on my left side, and within a week, I noticed a difference. My feet were still puffy, but not nearly as bad. It was such a relief!”

To maximize the benefits, try these additional tips for reducing swelling:

• Elevate your feet for 20–30 minutes a few times a day.
• Stay hydrated—drinking plenty of water helps your body flush out excess fluid.
• Avoid standing or sitting for long periods. Take short walks to keep blood flowing.
• Wear compression socks or stockings, especially if you’re on your feet a lot.
• Limit salty foods, which can contribute to water retention.

If your swelling is sudden, severe, or accompanied by headaches, vision changes, or upper abdominal pain, contact your provider immediately. These could be signs of preeclampsia, a serious pregnancy complication that requires medical attention.

What Are the Risks of Sleeping on the Right Side in the Third Trimester?

For most women, sleeping on the right side in the third trimester is safe and doesn’t pose significant risks. However, there are a few potential concerns to be aware of, particularly if you have certain high-risk conditions or notice symptoms that suggest reduced blood flow:

• Slightly reduced blood flow to the placenta. As mentioned earlier, the IVC runs along the right side of your spine. When you lie on your right side, the weight of your uterus can slightly compress this vein, which may reduce blood flow to your baby. For most women, this isn’t a problem, but if you have a condition like IUGR, preeclampsia, or placental insufficiency, your provider may recommend prioritizing the left side.
• Increased risk of heartburn. Sleeping on your right side can relax the lower esophageal sphincter (the muscle that keeps stomach acid in your stomach), making heartburn worse. If you’re prone to acid reflux, the left side may be more comfortable.
• Potential for dizziness or low blood pressure. Some women experience a drop in blood pressure when lying on their right side, which can cause dizziness or lightheadedness. This is more likely if you’re already prone to low blood pressure or dehydration. If you feel dizzy, try rolling to your left side or sitting up slowly.
• Possible link to stillbirth in high-risk pregnancies. While the overall risk is low, some studies suggest that women with high-risk pregnancies (such as those with IUGR or preeclampsia) may have a slightly higher risk of stillbirth if they sleep on their right side. A 2024 meta-analysis in The Lancet found that women with these conditions who slept on their right side had a small but statistically significant increase in stillbirth risk compared to those who slept on their left. If you have a high-risk pregnancy, talk to your provider about the best sleep position for you.

It’s important to note that these risks are relative—meaning the absolute risk of complications from right-side sleeping is still very low for most women. The bigger concern is sleeping on your back, which carries a higher risk of reduced blood flow and stillbirth, particularly in the third trimester. If you wake up on your right side, don’t panic. Simply roll to your left if you can, and focus on getting comfortable.

If you’re unsure whether right-side sleeping is safe for you, ask your provider. They can assess your individual risk factors and give you personalized advice. For example, if you have a posterior placenta (where the placenta is attached to the back of your uterus), you may have more flexibility with sleep positions than someone with an anterior placenta (where the placenta is attached to the front).

Tips for Staying Comfortable on the Left Side While Pregnant

Let’s be honest: sleeping on your left side all night isn’t always easy—especially when you’re used to sleeping on your stomach or back. The good news is that with a few adjustments, you can train your body to stay comfortable on your side. Here’s how:

1. Use a pregnancy pillow (or two).

A pregnancy pillow is a game-changer for side sleeping. These pillows are designed to support your belly, back, and hips, reducing pressure points and making it easier to stay on your side. Here are the most popular types:

• C-shaped pillow: Wraps around your body, supporting your head, belly, and back. Great for full-body support.
• U-shaped pillow: Similar to the C-shaped but with an extra “arm” to support your back. Ideal if you toss and turn a lot.
• Wedge pillow: A small, triangular pillow that props up your belly or back. Affordable and easy to travel with.
• Full-length body pillow: A long, straight pillow that you can hug or tuck between your knees. Versatile and budget-friendly.

If you don’t have a pregnancy pillow, try using regular pillows to create support. Place one between your knees to align your hips, one behind your back to prevent rolling, and one under your belly for extra support.

2. Try the “SOS” position.

SOS stands for “Sleep on Side,” and it’s the position recommended by the American College of Obstetricians and Gynecologists (ACOG). Here’s how to do it:

1. Lie on your left side with your knees slightly bent.
2. Place a pillow between your knees to keep your hips aligned.
3. Tuck a pillow under your belly for support.
4. If you’re prone to heartburn, prop up your upper body with an extra pillow or a wedge.

3. Stretch before bed.

Tight muscles can make side sleeping uncomfortable. Try these gentle stretches before bed to ease tension:

• Cat-Cow Stretch: On your hands and knees, alternate between arching your back (cat) and dipping it (cow). This relieves lower back tension.
• Seated Forward Fold: Sit with your legs extended and hinge at your hips to reach for your toes. This stretches your hamstrings and lower back.
• Child’s Pose: Kneel on the floor, sit back on your heels, and stretch your arms forward. This relaxes your back and hips.

4. Adjust your mattress.

If your mattress is too firm or too soft, it can make side sleeping uncomfortable. Ideally, you want a medium-firm mattress that supports your body without sagging. If you can’t replace your mattress, try these fixes:

• Add a mattress topper for extra cushioning.
• Place a folded blanket or towel under your hips for support.
• If your mattress is too soft, try sleeping on the floor (with a thin pad for comfort) to see if it helps.

5. Wear loose, breathable pajamas.

Tight clothing can restrict blood flow and make you feel overheated. Opt for loose, breathable fabrics like cotton or bamboo. Avoid elastic waistbands that dig into your belly or hips.

6. Stay hydrated (but not too much before bed).

Dehydration can worsen muscle cramps and make you feel achy. Drink plenty of water throughout the day, but taper off in the evening to avoid waking up for bathroom trips. Aim to stop drinking fluids about 1–2 hours before bed.

7. Try a warm bath or shower before bed.

A warm bath or shower can relax your muscles and ease tension, making it easier to get comfortable. Add a few drops of lavender essential oil (if approved by your provider) for extra relaxation.

8. Practice deep breathing.

If you’re feeling anxious or uncomfortable, try this simple breathing exercise:

1. Lie on your left side with a pillow supporting your belly and knees.
2. Place one hand on your belly and the other on your chest.
3. Take a slow, deep breath in through your nose, filling your belly with air.
4. Exhale slowly through your mouth, emptying your lungs completely.
5. Repeat for 5–10 breaths, focusing on relaxing your body with each exhale.

If you wake up on your right side or back, don’t stress. Simply roll back to your left side and use your pillows to get comfortable again. The goal is progress, not perfection.

Does Sleeping on the Left Side Help with Heartburn During Pregnancy?

Yes, sleeping on your left side can help reduce heartburn during pregnancy—and the science backs it up. Here’s why it works:

• Gravity keeps stomach acid down. When you lie on your left side, your stomach is positioned below your esophagus. This makes it harder for stomach acid to flow back up into your esophagus, reducing the risk of heartburn. In contrast, lying on your right side can relax the lower esophageal sphincter (the muscle that keeps acid in your stomach), making reflux more likely.
• Your stomach empties faster. Studies show that lying on your left side helps your stomach empty more quickly, which can reduce the amount of acid available to reflux. A 2022 study in Gastroenterology found that people who slept on their left side had significantly less acid exposure in their esophagus compared to those who slept on their right side or back.
• Less pressure on your stomach. As your uterus grows, it can push your stomach upward, increasing the risk of acid reflux. Sleeping on your left side helps relieve this pressure, giving your stomach more room to digest food comfortably.

One reader, Priya, shared her experience: “I used to wake up every night with a burning sensation in my chest. My doctor suggested sleeping on my left side with a wedge pillow to prop up my upper body. It took a few nights to get used to, but now I rarely have heartburn at night. It’s been a game-changer!”

To maximize the benefits, try these additional tips for managing heartburn:

• Eat smaller, more frequent meals. Large meals can overwhelm your stomach and trigger reflux. Aim for 5–6 small meals a day instead of 3 large ones.
• Avoid trigger foods. Common culprits include spicy foods, citrus, tomatoes, chocolate, caffeine, and carbonated drinks. Keep a food diary to identify your personal triggers.
• Don’t lie down right after eating. Wait at least 2–3 hours after eating before lying down or going to bed.
• Wear loose clothing. Tight waistbands can put pressure on your stomach and worsen reflux.
• Chew gum after meals. Chewing gum stimulates saliva production, which can help neutralize stomach acid.
• Try over-the-counter antacids. If lifestyle changes aren’t enough, talk to your provider about safe antacids like calcium carbonate (Tums) or famotidine (Pepcid). Avoid sodium bicarbonate (Alka-Seltzer) and magnesium trisilicate (Gaviscon), which aren’t recommended during pregnancy.

If your heartburn is severe or accompanied by difficulty swallowing, weight loss, or chest pain, contact your provider. These could be signs of a more serious condition like gastroesophageal reflux disease (GERD) or a hiatal hernia, which may require medical treatment.

Doctor Recommendations for Side Sleeping in Pregnancy

When it comes to sleep positions during pregnancy, doctors and midwives overwhelmingly recommend side sleeping—specifically on the left side—as the safest and most comfortable option. Here’s what the experts say:

American College of Obstetricians and Gynecologists (ACOG)

ACOG recommends that pregnant women sleep on their side (preferably the left) starting in the second trimester. They advise avoiding sleeping on your back after 20 weeks, as this can compress the IVC and reduce blood flow to your baby. ACOG also notes that while sleeping on the right side is generally safe, the left side is ideal for circulation and comfort.

Royal College of Obstetricians and Gynaecologists (RCOG)

The RCOG echoes ACOG’s recommendations, emphasizing that side sleeping is the safest position for both mother and baby. They suggest using pillows to support your belly and back, and they reassure women that it’s normal to wake up in different positions—just roll back to your side if you can.

National Health Service (NHS)

The NHS advises pregnant women to sleep on their side in the third trimester, citing evidence that this position reduces the risk of stillbirth. They note that sleeping on your back in the third trimester may increase the risk of stillbirth by up to 2.6 times, though the absolute risk remains low. The NHS also recommends avoiding sleeping on your stomach as your pregnancy progresses, as this can become uncomfortable and may reduce blood flow.

Mayo Clinic

The Mayo Clinic recommends side sleeping—especially on the left side—to improve blood flow to the placenta and reduce swelling. They suggest using pillows to support your belly, back, and knees, and they reassure women that it’s okay to switch sides if you wake up uncomfortable. The Mayo Clinic also advises avoiding sleeping on your back after the first trimester, as this can cause backaches, breathing problems, and low blood pressure.

Cleveland Clinic

The Cleveland Clinic emphasizes that side sleeping is the best position for pregnancy, with the left side being ideal for circulation. They recommend using a pregnancy pillow to stay comfortable and suggest propping up your upper body with a wedge pillow if you’re prone to heartburn. The Cleveland Clinic also notes that sleeping on your right side is safe for most women, but the left side is preferred if you have high blood pressure or other risk factors.

When to Talk to Your Provider

While side sleeping is generally safe, there are a few situations where you should check with your provider:

• You have a high-risk pregnancy (e.g., preeclampsia, IUGR, placental issues).
• You experience dizziness, shortness of breath, or reduced fetal movement when lying on your right side or back.
• You have severe back pain or sciatica that makes side sleeping difficult.
• You’re having trouble staying comfortable despite using pillows and other support.
• You notice sudden swelling, headaches, or vision changes, which could be signs of preeclampsia.

Your provider can give you personalized advice based on your medical history and pregnancy. For example, if you have a posterior placenta, you may have more flexibility with sleep positions than someone with an anterior placenta. If you have gestational diabetes, your provider may recommend additional monitoring to ensure your baby is getting enough oxygen and nutrients.

What If You Can’t Stay on Your Side?

If you’re struggling to stay on your side, don’t stress. The most important thing is to avoid sleeping on your back for long periods. If you wake up on your back, simply roll to your side and go back to sleep. You can also try these strategies:

• Use a pregnancy wedge. Place a wedge pillow behind your back to prevent rolling onto your back.
• Try a tennis ball trick. Sew a tennis ball into the back of your pajama top. The discomfort will remind you to roll back to your side if you start to roll onto your back.
• Set an alarm. If you’re worried about rolling onto your back, set an alarm for every 2–3 hours to check your position and adjust if needed.
• Sleep in a recliner. If you’re really struggling, try sleeping in a recliner at a 45-degree angle. This can help keep you off your back while still allowing you to rest.

Remember, the goal is to get as much rest as possible. If you’re exhausted, your body will naturally prioritize sleep over position. Don’t let fear of “doing it wrong” keep you up at night. As one midwife put it: “A well-rested mom is a healthy mom. If you wake up on your right side, it’s not the end of the world. Just roll back to your left and try again.”

Best Pregnancy Pillow for Side Sleeping

If you’re serious about side sleeping, a pregnancy pillow is a must. These pillows are designed to support your growing belly, relieve pressure on your hips and back, and help you stay comfortable on your side all night. But with so many options on the market, how do you choose the right one? Here’s a breakdown of the best pregnancy pillows for side sleeping, based on comfort, support, and ease of use:

How to Choose the Right Pregnancy Pillow

When shopping for a pregnancy pillow, consider these factors:

• Your sleep style: If you toss and turn a lot, a C- or U-shaped pillow may be best. If you prefer to hug a pillow, a full-length body pillow could be ideal.
• Your pain points: If you have back pain, look for a pillow with lumbar support. If you have hip pain, choose a pillow with memory foam or a soft, supportive fill.
• Your bed size: If you have a small bed, a wedge or full-length pillow may be more practical than a large C- or U-shaped pillow.
• Your budget: Pregnancy pillows range from $20 to $120. Set a budget before you shop, and remember that a higher price doesn’t always mean better quality.
• Ease of cleaning: Look for a pillow with a removable, machine-washable cover. Pregnancy can be messy, and you’ll want to keep your pillow clean.

Top-Rated Pregnancy Pillows (2026)

Here are some of the top-rated pregnancy pillows on the market in 2026:

• Best Overall: Leachco Snoogle Total Body Pillow (C-shaped, $70–$90). This pillow is a favorite among pregnant women for its versatility and support. It’s adjustable, machine-washable, and great for nursing postpartum.
• Best for Back Pain: PharMeDoc Pregnancy Pillow (U-shaped, $60–$80). This pillow provides full-body support and is especially helpful for women with back pain or sciatica.
• Best Budget: Boppy Side Sleeper Pregnancy Pillow (full-length, $30–$50). This affordable pillow is great for hugging and can be used for nursing after baby arrives.
• Best for Travel: Hiccapop Pregnancy Wedge Pillow ($25–$35). This compact wedge is perfect for supporting your belly or back on the go.
• Best for Plus-Size Women: Queen Rose Pregnancy Pillow (extra-large C-shaped, $80–$100). This pillow is longer and wider than most, making it ideal for taller or plus-size women.

How to Use Your Pregnancy Pillow

Once you’ve chosen your pillow, here’s how to use it for maximum comfort:

1. For side sleeping: Place the pillow along your body with the curve under your head and the long end between your knees. Hug the top part of the pillow to support your belly.
2. For back support: If you’re using a C- or U-shaped pillow, place the curve behind your back to prevent rolling onto your back.
3. For heartburn relief: Prop up your upper body by placing the pillow under your head and shoulders. This helps keep stomach acid down.