The best body pillows for side sleepers

A body pillow supports the two joints a head pillow can't reach: your top arm and your top knee. Without support, the top leg slides forward and twists the pelvis, and the top arm rolls the shoulder in. Cleveland Clinic suggests a pillow between the legs to stop the upper leg pulling forward and twisting the torso, and pillows under a sore top arm to keep it straight and neutral^[5]. A body pillow does both jobs in one, and hugging something in front of you makes it harder to roll onto your stomach.

The evidence is thin. A scoping review found side lying was generally linked to fewer spinal symptoms, but only 4 of 4,186 screened articles made it into the review^[6]. No trial has tested body pillows for pain in adults who aren't pregnant. The case rests on clinical advice and low risk. Treat it as a comfort tool, not a treatment.

Set your head pillow first, then lay the body pillow down your front, then hook your top knee over it. Our loft guide covers head pillow height.

1. 1

   Set your head pillow

   It should fill the gap between your ear and the mattress so your head doesn't tip down.

2. 2

   Lay it down your front

   Top end at chest or chin height, the rest running toward your feet.

3. 3

   Hug with your top arm

   Rest the forearm on it so the top shoulder stays stacked instead of rolling forward.

4. 4

   Hook the top knee over

   Bend it slightly and rest it at about hip height, so the top leg can't drop and twist your pelvis.

5. 5

   Stretch out a little

   Keep your thighs roughly in line with your torso. A tight fetal curl puts more pressure on the lower back.

6. 6

   Switch sides on purpose

   Sleeping on one side every night can build imbalances. Move the pillow over, or use a U-shape that's on both sides.

Steps 5 and 6 follow Cleveland Clinic's spine advice, which also warns against the fetal position^[5].

Straight suits most side sleepers. Pregnancy is where the curved shapes earn their bulk. In BabyGearLab's hands-on tests of pregnancy pillows, testers found the straight I-shape took the least room in bed but struggled to cover front and back, and shifted once they moved^[7]. They found the U the least adaptable shape, though it supports your back and belly at the same time, and praised their top C-shape for keeping the natural spacing between the legs.

• C-shape: one curve under your head, down your front and between your knees. Sleep Foundation notes it isn't very bulky and can be folded to support the belly, back or knees^[8]. You get little support behind you.
• J-shape: a straight pillow with a hook at the top that wraps under your head, so one pillow supports head, arm and knee.
• Wedge: a small, firm triangle tucked under the bump or behind the back. It's the most compact pregnancy pillow but gives no full-body support^[8].

Bed space and partners

Measure your side of the bed before you buy a U. BabyGearLab measured the Momcozy U at 27.6 inches (70 cm) wide and the INSEN C at 28 inches^[7]. A queen mattress is 60 inches wide and a full is 54^[9], so either shape takes about half a queen and more than half a full. A straight pillow is 20 inches wide^[4] and lies lengthwise against you. If you share a full, or your partner already feels squeezed, go straight or wedge. If you turn over several times a night, a U saves you hauling a pillow across the bed each time.

• Length: the standard straight body pillow is 20 × 54 inches^[4]. It should reach from your chin or shoulder to below your knees. 54 inches suits most adults. If you're tall and the pillow ends above your knee, look for 60 inches.
• Thickness: thick enough that your top knee rests level with your hip. Too thin, and the knee still drops. Wider hips need more height.
• Adjustability: fill you can add or remove (the Coop) lets you thin the pillow for a slim hug or keep it full for firm knee support. That also helps in pregnancy, when your shape changes month to month.

The knee end helps your hips and lower back. The hug end helps your top shoulder. If hips are your only issue, a smaller knee pillow is cooler and stays put. For a sore top shoulder, hugging the top end keeps the arm supported in a neutral position, and the full setup is on our shoulder pain page. Pain that wakes you night after night, or follows an injury, needs a clinician, not a new pillow.

From 28 weeks, go to sleep on your side. Either side is fine. The NHS says the safest position to go to sleep is on your side, left or right^[10]. Australian and New Zealand guidance asks women to settle on either side from 28 weeks for every sleep: at bedtime, after waking in the night, and for daytime naps^[2]. ACOG suggests side sleeping through the second and third trimesters, because lying on your back may compress a major blood vessel, which can make you feel dizzy and may reduce blood flow to the baby^[11].

Why 28 weeks

The advice comes from case-control studies that compared women who had a late stillbirth with women whose pregnancies continued. A meta-analysis of individual data from 851 stillbirths and 2,257 controls found that going to sleep on the back from 28 weeks was linked to 2.63 times the odds of late stillbirth compared with the left side^[1]. Going to sleep on the right side carried similar odds to the left. The UK MiNESS study (291 cases and 733 controls across 41 maternity units) found a similar link, with an adjusted odds ratio of 2.31^[12]. There's a plausible mechanism: MRI scans late in pregnancy show the inferior vena cava, the large vein carrying blood back from the lower body, about 85% narrower on the back than on the left side^[2].

Keep the risk in proportion

The absolute risk is small, and most women already go to sleep on their side. Late stillbirth affected about 2.6 per 1,000 births in Australia in 2019^[2]. In the meta-analysis, only 3.2% of women in the comparison group went to sleep on their back, and the authors estimated that 5.8% of late stillbirths might be avoided if every woman from 28 weeks settled to sleep on her side^[1]. These studies show a link, not proof of cause, and they rely on women recalling how they fell asleep, often after a loss^[12]. Earlier in pregnancy the picture is reassuring. In a US cohort of 8,706 first-time mothers, going to sleep on the back or right side through 30 weeks wasn't linked to stillbirth, small babies or high blood pressure disorders^[13]. It had few stillbirths and stopped short of late pregnancy, where the 28-week advice applies.

Not reliably. In a randomized trial in late pregnancy, a pillow built for the job didn't reduce back sleeping. Researchers in Melbourne had women in late pregnancy spend one week with a U-shaped pillow whose firm back rail was meant to stop them rolling over, and one week with their own pillows. Sensors tracked 469 nights from 35 women^[3]. They spent a median 16.0% of the night on their back with the special pillow and 13.0% with their own, about an hour either way. Women reported falling asleep on their back on only 0.6% of nights, but sensors recorded it on 7.9%, so it's easy to underestimate.

Outside pregnancy the picture is a little better. In a trial of 20 healthy volunteers, a wedge-and-body-pillow system kept people on their assigned side for more than half of a six-hour test, while people on a plain wedge or a flat bed spent more time on their backs than on either side^[16]. The trial was small, and one author was affiliated with Amenity Health, which makes such a system. The practical lesson for pregnancy: use the pillow for comfort, settle on your side at the start of each sleep, and roll back over if you wake on your back.

Probably, for comfort, though the trial evidence is small and unblinded. Poor sleep is common in pregnancy: a meta-analysis of 24 studies and 11,002 women found 45.7% had poor sleep quality, and sleep got worse from the second to the third trimester^[17]. In a randomized trial of 75 first-time mothers in Turkey, women given a pregnancy pillow from 29 to 30 weeks reported better sleep (an average sleep-quality score of 4.03, against 8.12 without one, where lower is better) and more comfort^[18]. The women knew which group they were in and rated their own sleep, so treat the size of that effect with caution. Sleep Foundation puts it fairly: a pregnancy pillow isn't a necessity, but it can help if your sleep is disturbed^[8].

Setting up for common pregnancy aches

• Belly and back: ACOG suggests keeping one or both knees bent, with a pillow between your knees and another under your belly, or a full-length body pillow^[11]. A C or U does both with one pillow.
• Pelvic girdle pain: it affects about 1 in 5 pregnant women. Physiotherapists advise a pillow between your knees when lying on your side, keeping your knees together as you turn over, and trying turning via your hands and knees^[19]. A U-shape suits this, because you roll over between its two rails instead of dragging a pillow with you. For hip support in general, see knee pillows.
• Heartburn: the NHS suggests propping up your head and shoulders and says sleeping on your left side can help^[20]. In 57 people referred for reflux testing (not pregnant), acid exposure was a median 0.0% of time on the left side versus 1.2% on the right^[21]. A wedge under your upper body plus a body pillow to hold you on your left side combines both.

Hugging a big pillow traps heat, and the cover matters as much as the fill. Heat during sleep increases wakefulness and cuts deep and REM sleep^[22]. In BabyGearLab's side-by-side testing, velvet covers like the Momcozy's retained the most heat^[7]. Polyester fiberfill is inexpensive, hypoallergenic and easy to clean. Some memory foams restrict airflow and hold heat, and cotton covers breathe well^[8]. If you run hot, pick a cotton cover and a thinner fill, and see our cooling guide.

Wash the cover often, because a body pillow sits against your face and arms all night. New synthetic pillows in one study had no detectable dust mite allergen, but levels had built up within three months of use^[23]. The American Academy of Allergy, Asthma & Immunology advises washing bedding weekly in hot water (130°F, 54°C) and using allergen-proof covers on pillows that can't be washed regularly^[24]. Check care labels before you buy:

• Coop and Snuggle-Pedic: the whole pillow, shredded-foam fill included, can go in the washing machine.
• Momcozy, Queen Rose and INSEN: the covers zip off and machine wash, and the INSEN's long zipper also lets you add or remove fill^[7,25]. The fiber inserts are bulky, so the cover is the part you'll wash most.
• Utopia: spot-clean only. Put it in a washable body-pillow case from day one.

Your pregnancy pillow stays useful after the birth, but keep it out of your baby's sleep space. The NHS says lying on your side to breastfeed is a good position after a cesarean or difficult delivery, with pillows behind your back, and advises keeping the pillow under your head away from your baby's face^[26]. A body pillow behind your back and between your knees does that job well, as long as it stays on your side of the bed.