Swaddling can help some newborns feel calm and settled, but how you wrap your baby matters. A swaddle that holds the legs straight and tightly together can restrict natural hip movement during an important period of development. Hip-healthy swaddling takes a different approach: the upper body can be wrapped securely while the hips and knees still have enough room to bend and move.
The International Hip Dysplasia Institute (IHDI) recommends allowing a baby's hips to remain slightly bent and spread apart rather than forcing the legs into a straight, extended position.
Hip position is only one part of safe swaddling, however. A swaddled baby should always be placed on their back to sleep, and swaddling should stop as soon as the baby shows signs of trying to roll.
What Does "Hip-Healthy Swaddling" Mean?
Hip-healthy swaddling means wrapping your baby in a way that does not force their hips and legs into a fixed, straight position.
Newborns naturally tend to hold their legs bent rather than stretched straight down. For healthy hip development, the IHDI recommends that the hips remain in slight flexion and abduction during swaddling. In simpler terms, your baby's thighs should be able to bend upward and move somewhat apart, with the knees also slightly bent.
This does not mean the entire swaddle needs to be loose. The fabric around the upper body can be comfortably snug so that the wrap stays secure. The American Academy of Pediatrics (AAP) advises leaving enough room to fit about two or three fingers between your baby's chest and the swaddle.
Below the waist, however, there should be noticeably more freedom. Your baby should be able to:
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Bend their knees.
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Bring their legs upward.
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Move their thighs apart.
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Change the position of their hips and legs inside the lower part of the swaddle.
Think of hip-healthy swaddling as secure around the torso, roomy around the hips and legs.
Why Can Tight Swaddling Around the Legs Be a Problem?
A newborn's hip joint is still developing. The top of the thigh bone sits inside a socket in the pelvis, and the relationship between these structures during early infancy matters for normal development.
Traditional swaddling methods sometimes straighten a baby's legs and bind them tightly together. According to the IHDI, holding the hips and knees in this extended position can increase the risk of developmental dysplasia of the hip (DDH) and hip dislocation.
DDH describes a range of problems in which the hip joint does not develop or fit together normally. Tight leg swaddling is not the only factor associated with DDH, and using a swaddle does not automatically mean a baby will develop a hip problem. The concern is specifically with prolonged positioning that forces the legs straight and together.
That distinction is important. Parents do not necessarily need to avoid swaddling altogether simply because they are concerned about hip health. Instead, the goal is to avoid restricting the lower body in an unnatural position.
Why can tight swaddling around the legs be a problem?
How to Swaddle Your Baby Without Restricting Their Hips
You can use a thin swaddling blanket while still leaving plenty of room around your baby's hips. The exact wrapping technique can vary, but the basic principles should remain the same.
1. Position the blanket
Spread a lightweight swaddling blanket on a flat surface and fold down the top corner. Place your baby on their back with their shoulders near the folded edge and their head completely above the blanket.
2. Secure the first side around the upper body
Bring one side of the blanket across your baby's chest and tuck it securely underneath their body.
The wrap should feel comfortably snug around the torso without pressing tightly on the chest. You should be able to slide roughly two or three fingers between the baby's chest and the swaddle.
3. Leave the legs in their natural position
This is the key step for hip-healthy swaddling.
Do not pull your baby's legs straight before folding the bottom of the blanket. Let the knees remain bent naturally and make sure there is room for the thighs to move upward and outward.
The lower portion should form more of a loose pouch around the legs than a tight wrap around each leg.
4. Fold the bottom loosely
Bring the lower part of the blanket upward without pressing the legs together or flattening them against the mattress.
The IHDI advises leaving enough room for the baby's hips and legs to move freely rather than tightly wrapping the lower body.
5. Secure the remaining side
Bring the remaining corner across the upper body and tuck it underneath your baby, keeping the fabric securely away from the face.
Once finished, check the lower half again. Your baby's legs should not look stretched straight down inside the wrap.
For sleep, always place a swaddled baby flat on their back on a firm sleep surface without pillows, toys or other loose objects around them.
How to swaddle your baby without restricting their hips
How Can You Tell If the Swaddle Is Too Tight Around the Hips?
There is no specific "two-finger rule" for the hips like the commonly used chest-fit check. Instead, focus on whether the swaddle allows natural lower-body movement.
The swaddle may be too restrictive if:
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Your baby's legs are held straight instead of bent.
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Their thighs are pressed tightly together.
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The fabric pulls the legs downward when you finish wrapping.
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There is little or no room for the knees to move upward.
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The baby's lower body seems fixed in one position.
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A swaddle sack feels stretched tightly across the thighs or hips.
A better sign is that the lower section looks roomy enough for your baby to bend and reposition their legs.
You also do not need to deliberately force your baby's legs into an exaggerated position. Hip-healthy swaddling is about allowing movement, not holding the hips in a rigid "correct" pose.
If your baby has been diagnosed with hip dysplasia, is wearing a Pavlik harness or another orthopedic device, follow the positioning and clothing instructions provided by their pediatric orthopedic team rather than using a standard swaddling technique. IHDI specifically advises avoiding swaddling that brings the legs together during hip dysplasia treatment.
Are Swaddle Sacks and Wearable Swaddles Hip-Healthy?
They can be, but the design and fit matter.
A commercial swaddle sack should provide a roomy lower section so that the baby's hips can bend and the thighs can move apart. The IHDI notes that commercial swaddling products should provide plenty of space around the legs and feet. It also warns that even a swaddle product can restrict hip movement if it is too small or tightened around the thighs.
When evaluating a wearable swaddle, look for:
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A wide or roomy pouch around the hips and legs.
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Space for the knees to remain bent.
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Freedom for the thighs to move apart.
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The correct size for your baby's current measurements.
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A design that does not cinch tightly across the upper thighs.
Do not rely only on marketing terms. Check how the garment actually fits your baby and follow the manufacturer's sizing and use instructions.
Also distinguish between a swaddle sack, which restricts the arms or upper body, and a regular sleep sack, which leaves the baby's arms and body free to move. The AAP recommends stopping swaddling, including wearable products that compress the arms, chest and body, as soon as a baby shows signs of trying to roll over. Some babies begin attempting to roll as early as around 2 months. A non-swaddling sleep sack that allows free movement can continue to be used after the swaddling stage.
Weighted swaddles should not be used. Current AAP safe-sleep guidance advises against weighted swaddles, weighted blankets and other weighted items on or near sleeping infants.
FAQs
Can swaddling cause hip dysplasia?
Swaddling itself is not necessarily the problem. The concern is swaddling that repeatedly holds a baby's hips and knees straight while pressing the legs together. This position has been associated with an increased risk of hip dysplasia and dislocation. Hip-healthy swaddling leaves room for the hips and knees to bend and move.
How loose should a swaddle be around a baby's legs?
There is no universal measurement. Instead, make sure your baby's knees can bend upward and their thighs can move apart inside the swaddle. The lower section should behave more like a roomy pouch than a tight wrap around the legs.
Should a newborn's legs be straight when swaddled?
No. You should not intentionally pull a newborn's legs straight and bind them together. Allow the legs to remain naturally bent with room for hip movement.
When should I stop swaddling my baby?
Stop swaddling as soon as your baby shows signs of trying to roll, rather than waiting for a specific age. The AAP notes that some babies may begin working on rolling at around 2 months. Once those signs appear, transition away from any swaddle that restricts the arms, chest or body.
Is hip-healthy swaddling also safe sleep?
Hip-healthy positioning addresses one aspect of swaddling, but it does not replace safe-sleep practices. A swaddled baby should still sleep on their back on a firm, flat sleep surface with loose bedding, pillows and soft objects kept out of the sleep space. Swaddling itself is not a strategy for preventing SIDS.
Conclusion
The basic idea behind hip-healthy swaddling is simple: keep the upper body comfortably secure while giving the hips and legs room to move naturally.
Avoid wrapping your baby's legs straight down or pressing the thighs together. Instead, leave enough space for the knees to bend and the hips to move upward and outward. Whether you use a traditional blanket or a wearable swaddle, check the fit around the lower body rather than assuming that a product is automatically hip-friendly.
And remember that hip health is only one part of safe swaddling. Always place your baby on their back for sleep, use a firm and flat sleep surface, keep loose objects out of the sleep space and stop swaddling at the first signs that your baby is trying to roll.
