There are so many decisions when you have a newborn and so many things to get your head around, especially when it comes to newborn sleep. Sleep becomes your number 1 priority, because if your newborn isn’t sleeping, you won’t be sleeping. And without sleep, life kinda sucks.
So you want your baby to sleep well, which means being comfortable as well as safe. Your baby’s sleepwear can play a big part in both – but what’s the best option? Swaddle or sleep sack for a newborn? Oh, and then there are swaddle sleep sacks?
Confused? I was.
Maybe you’re not even sure what exactly these things are. And walking into the baby section of any store will give you endless newborn sleepwear options; it can all be a bit overwhelming. Don’t worry, you’re in the right place. We will break down the differences and the benefits of swaddles and sleep sacks so you can finally get on with helping your newborn with a good nights sleep.
You’ll learn if a sleep sack or swaddle is better for your newborn.
What is a swaddle and what is swaddling?
If you are a new parent, the term swaddling might sound a bit foreign, or you may have heard about it but not have much idea what it is.
The technique of swaddling has been around pretty much since day dot but, thank goodness, the reasons for swaddling, as well as the techniques used, have evolved. In Roman times babies were swaddled, by binding them in long strips of muslin, often to a “cradle-board” (plank of wood), to keep them warm and help the limbs grow straight – day and night until they were at least 9 months…. Shocking, right?!
Not surprisingly, this wasn’t actually all that good for a baby and in the 18 century aDr Cadogan tried, but failed, to abolish swaddling. However, now it’s strongly back in favor in the Western world, the reasons to swaddle, both sleep-related.
Muslin is still a popular choice in terms of swaddle fabric for its softness against a newborn’s delicate skin and the aim is to keep baby in a tight, secure and comforting hold but that’s where the similarities end.
These days swaddling is done with a simple large square of fabric (like a receiving blanket but bigger) or with baby-friendly material with sewn pre-folds, velcro or zips to make swaddling that little bit easier.
The swaddle techniques used and the guidelines for swaddling ensure it’s safe, both in terms of a newborn’s growing body and limbs and any risk of Sudden Infant Death Syndrome or SIDS.
What are the benefits of swaddling a newborn?
Swaddling creates deep pressure touch, helping your newborn feel safe and reminds them of the womb. Imagine, your newborn has been tightly curled up inside the womb for 9 months – the freedom of all that space with flailing legs and arms must feel quite scary. Swaddling mimics the womb.
So, the number 1 reason to swaddle: it calms and soothes and helps get baby ready to sleep.
For this reason, babies who struggle with colic will benefit from swaddling. Same goes for little ones that never want to be put down; swaddling mimics your touch and the close contact of your body.
The number 2 reason to swaddle: it prevents unnecessary wakings at night, specifically due to the “Moro” or startle Reflex
The Moro reflex turns a newborn into a startled starfish for no apparent reason – if you’ve seen the Moro reflex in action you’ll know exactly what I’m talking about. It’s a newborn reflex that has little purpose these days. It’s a remnant of our tree-swinging days when it helped babies cling to mom.
It can be strong enough to wake and even upset a newborn. An effective and correctly fitted swaddle will keep the arms tucked securely to the side, preventing the Moro Reflex from disturbing. Baby will stay snug and asleep.
There’s scientific evidence that swaddling reduces the number of night wakings. (Source) Can’t say better than that, right?
Do I have to swaddle my newborn?
Absolutely not – it’s entirely up to you. Having said that, you’d be mad not to give one a go. A newborn can sleep without a swaddle but chances are they’ll sleep a lot better with one.
You may have a baby who is naturally cool, calm and collected, settles to sleep easily and has a very mild Moro reflex that rarely disturbs. In which case swaddling may not benefit your newborn as much.
Or you may feel that swaddling doesn’t suit your newborn, baby hates to be swaddled or you can’t get the silly thing to stay on and baby struggles and struggles and struggles until finally escaping.
These are all common swaddle problems which are covered in our free online swaddle course (complete with video tutorials and printables). Sign up now to learn the correct way to swaddle, so that baby does stay wrapped up, even if you have a swaddle hater or mini Houdini on your hands.
Should I swaddle my newborn all day
Absolutely not. A newborn needs to get used to the newfound freedom of the outside world. This facilitates the development of muscle tone, balance and coordination.
For this reason, you also want to limit the use of car seats.
Get baby wrapped up and swaddled when due a sleep or to calm and soothe if gassy, irritable or overtired.
A “sleep sack”, “sleeping bag” or “wearable blanket” is alternative sleepwear to a swaddle
What is a sleep sack?
A sleep sack is often called a sleeping bag or wearable blanket. Hopefully, these alternative terms give you quite a clear idea of what it one is, otherwise the picture above will clarify.
There is no swaddling aspect to a sleepsack; it’s simply a way of adding an extra layer to baby without using a blanket since loose blankets in the cot aren’t safe for a baby.
Loose items of bedding and other items from blankets, pillows, teddies as well as cot bumpers shouldn’t be present in baby’s drib or bassinet, as they pose a risk of suffocation. Check out the full list of Safe Sleep guidelines here.
What are the benefits of a sleep sack?
The key advantage of a sleep sack is the safety aspect vs. a blanket.
Versus a swaddle, there are also benefits:
- you can get different thicknesses of sleep sacks – they’re tog-rated like a duvet – so it’s easier to keep baby warmer if necessary (with swaddling you’d need to double swaddle
- a sleep sack is much easier to put on whereas swaddling effectively and correctly does take a bit of learning and skill, if you’re using a simple swaddle blanket
- sleep sacks also offer easy access to the diaper area making nighttime changes quicker; the same is only true of some of the pre-folded swaddle sacks
- a sleep sack might be enough to dampen the Moro reflex for newborns with just a mild reflex, but for most newborns it won’t be nearly as effective as a well-fitted swaddle
Without the deep pressure touch that swaddling creates, a swaddle is always going to trump a sleep sack for the newborn phase.
Can I use a sleep sack instead of swaddling?
You can. A sleep sack is a safe alternative to swaddling; newborns can sleep in sleep sacks.
So if your baby doesn’t appear to benefit from swaddling due to a mild Moro reflex, you’ve really given up on getting it to stay on or you’re absolutely convinced baby hates the swaddle (surely not after this free swaddle course?!) then a sleep sack is the way to go.
When baby can no longer be swaddled (once becoming more mobile and able to turn from a back-lying position onto the front) then you need to transition to a sleep sack; the arms need to be free once baby is moving so she can’t be stuck on her front, risking SIDS. More details covered later on in this article.
What’s the difference between a swaddle blanket and a sleep sack?
A swaddle blanket offers that deep pressure touch; with arms held close to the body, baby experiences the tight hold she would have experienced in the womb. This calms, comforts and prevents the Moro Reflex from disturbing.
The swaddle blanket itself is a simple square of material that you use to wrap baby up into a neat swaddle (burrito style).
A sleep sack offers little of that deep pressure touch. It’s a baby version of a sleeping bag; arms are out to the side via arm holes, free to move around and disturb when the Moro Reflex strikes.
A sleep sack can also be called a wearable blanket, which describes them well too; it eliminates the need for a loose blanket in the cot, a big no when it comes to safe sleep.
What the heck is a “swaddle sleepsack?!”
If you like the idea of swaddling for those sleep-related benefits (how can you not) but the thought of getting those origami folds right is too much, or you’ve tried swaddling and failed, you need to try a swaddle sleepsack. Sometimes also termed a swaddle sack.
A hybrid swaddle sleep sack combines the swaddling effect of a swaddle blanket with the ease of use of a standard sleep sack
A swaddle sleepsack hybrid is far more structured than a sleep sack, with pre-folds, zips or velcro to offer swaddling properties without need to learn any complicated folding techniques.
Benefits of the hybrid swaddle sleepsack
A swaddle sleepsack is effectively a cross between a swaddle blanket and a sleep sack, giving you the best of both worlds:
- soothes and calms with a tight, close hold that mimics the womb as well as preventing disturbance from the Moro Reflex, just like a well-fitted swaddle will
- is much easier to use, with zips, velcro and/or pre-folds, like a sleep sack
With a hybrid swaddle sleepsack, you get the ease of use of a sleep sack combined with the snugness and sleep benefits of a swaddle.
In addition, while swaddle blankets need fully removing for diaper changes, many swaddle sleepsacks are designed to allow easy access to the diaper area without having to unwrap baby’s arms.
Any drawbacks of the hybrid swaddle sleepsack?
There are two main issues:
#1 The varying effectiveness of different swaddle sleepsacks for different babies
Whereas with a swaddle blanket you can try multiple different swaddle techniques to see which one works best for your newborn, there’s only one way to use a specific swaddle sleepsack. If it doesn’t fit your baby well or isn’t effective in soothing, calming or fail to control the Moro Reflex, you’re back to the drawing board
#2 They’re often sized, so you may need a 2 or 3 just to get baby through the newborn phase
Again, this is contrast to a swaddle blanket which can last your baby all the way through the newborn phase and beyond or whenever swaddling is no longer safe (when baby starts to roll and turn)
Are swaddle blankets & swaddle sleep sacks safe for a newborn?
Swaddling reduces night wakings – this is exactly why you want to swaddle. Babies stay longer in their deepest sleep stage, “quiet sleep” and show fewer spontaneous arousals when swaddled (source).
But these arousals are there for self-protection; they allow the brain to check-in that all is ok (which includes checking for a drop in oxygen levels) and come into full consciousness if necessary.
So there was natural cause for concern that swaddling may be risk factor in SIDS, but as long as safe sleep guidelines are followed, swaddling with a swaddle blanket or swaddle sleep sack are safe for a newborn to sleep in.
Minimizing the risk of SIDS when baby is swaddled
The full list of recommendations to swaddle safely are:
1) Back to sleep
Baby must, must, must sleep on her back – even more important when baby is swaddled, as per the above.
2) Ditch the swaddle when baby starts to roll and turn over
Because baby must, must, must sleep on her back…
3) Ensure swaddle is tight and secure
You don’t want it to come loose and become a suffocation hazard:
You need to be able to fit two fingers comfortably between your baby’s chest and the blanket.
So, if you’re wondering, can you swaddle a baby too tightly? The answer is yes, remember the two-finger check to ensure it’s not too tight.
4) Beware of overheating
Babies cannot regulate their temperature easily, and of course are unable to easily communicate when too hot or cold.
Key is to monitor how hot or cold your baby is and look for the signs of overheating:
- tummy and/or back of neck feel hot to touch (hands and feet will naturally feel cooler)
- sweatiness and clamminess
- damp hair (due to sweat)
- flushed cheeks
- rapid breathing
- heat rash
So when swaddling with either a swaddle blanket or swaddle sleep sack, keep an eye out.
If baby feels hot, remove a layer and check again 10 minutes later. You can also open windows/doors and turn on a fan (not directly over your newborn) to get some air circulating helping to cool baby.
Swaddle blankets, swaddle sleep sacks & hip health
The traditional swaddling techniques of binding baby with legs straight and fully extended was extremely damaging, often resulting in hip dislocation or dysplasia – no wonder having been culled up in the womb with legs all tucked up.
Safe swaddling guidelines to protect the hips
The swaddle blanket or sleep sack needs to be loose around the hips so the legs can stay in their natural position when baby is lying on her back, bent up and out. Think frog on its back. This means baby will be able to move her legs freely.
For more info. on hip issues and hip healthy swaddling check out this article from the International Hip Dysplasia Institute.
Are sleep sacks safe for a newborn to sleep in?
Sleep sacks are designed for your newborn to sleep in and are safe as long as:
- baby wears the correct size – a sleep sack that’s too big could start to ride up with a wriggly baby, risking suffocation. A sleep sack that’s too small could restrict leg movement, which wouldn’t be safe from a hip development point of view
- baby has her arms free and through the armholes – again, otherwise it could ride up and over baby’s face
Which is better for my “Fourth Trimester” baby (newborn): swaddle blanket, swaddle sleepsack or sleep sack?
Familiar with the term “fourth trimester”? Babies are born developmentally immature vs. every other species so the thought is baby would have done better staying in utero another 3 months. But, you know, large head, small passage of entry into the world… any longer and birth would be almost impossible.
For this reason, mimicking the comforting sensations of the womb are particularly important during the fourth trimester or newborn phase. And this is where the swaddle comes into its own, by recreating a very important environmental aspect of the womb: that deep pressure touch. Hence, swaddling has such benefits in the calming, soothing and sleep departments.
So it should be no surprise that a swaddle blanket or swaddle sleepsack, trump a sleep sack any day.
Swaddle blanket or swaddle sleepsack?
This is nothing more than personal choice – you can learn the right way to swaddle effectively with a simple swaddle blanket or take the plunge and invest in a swaddle sleepsack.
Swaddle sleepsacks normally do have the advantage of being able to do discreet diaper changes with designs that avoid having to completely unwrap baby, but other than that they’re on a level playing field.
I, for one, am definitely for swaddle blankets – once you’ve found an easy technique, there will be no stopping you…. Find out my fail-safe swaddle technique by taking this free swaddle course:
What to consider when choosing a swaddle or sleep sack for newborn
Choosing the perfect swaddle or sleep sack for your newborn can seem daunting, but it doesn’t have to be. I have listed all the factors that you should pay attention to when choosing a swaddle, sleep sack or swaddle sleepsack for your baby.
#1 Fabric type
Best fabrics for swaddle blankets & swaddle sleep sacks
Like any fabric that’s close or in contact with your newborn’s delicate skin, you want to go for natural fibers such as cotton, bamboo or a blend of the two.
The correct term for fabrics made from bamboo is actually “Viscose rayon”, “rayon” or “rayon made from bamboo”.
Both are breathable, unlike synthetic materials, which will keep baby comfortable as well as minimize the risk of overheating.
Organic cotton is preferable over regularly grown cotton since it’s softer still and is eco-friendly.
For even more softness, try viscose rayon, which is better still at wicking away moisture than cotton. It may also have some natural anti-bacterial properties, although the chemical processing of raw bamboo into fabric is thought to remove much of this. (Due to the use of chemicals to produce bamboo fabric, bamboo fabrics can never be classified as “organic”.)
Weave type for swaddle blankets
There’s either traditionally used muslin, which has a large and loose weave, allowing plenty of air flow. Muslin swaddles are ideal for warmer weather.
For cooler weather opt for jersey knit which has a much tighter weave often with some added spandex for a bit of stretch.
Best fabrics for sleep sacks
Since a sleep sack is loose fitting and little of it is in close contact with your newborns skin, fabric choice is not as important. However, natural materials are still best as they’re breathable and therefore safer and more comfortable.
Again, cotton or viscose rayon/rayon/rayon made from bamboo are first choice.
Sleep sacks are also available in different tog ratings; the filling is often a synthetic material which is fine.
#2 Temperature control for newborn sleep sacks or swaddling
Overheating is a risk factor in SIDS. Besides, your newborn won’t sleep well if too hot or cold. So check baby is a comfortable temperature, as per the guidelines earlier.
The main way of ensuring baby is a comfortable temperature is to layer baby correctly under the swaddle or sleep sack.
For the recommended ambient room temperature of 16-20 degrees Celcius or 61-68 degrees Fahrenheit, your newborn will probably be the correct temperature in the following:
Bodysuit/onesie + pyjamas/sleepsuit/one-piece + swaddle blanket or swaddle sleep sack
For appropriate clothing combinations for other temperatures, check out the “Layering baby up” section in this post: What should a newborn baby wear to sleep in (the link should jump you straight to that section).
In addition, use a sleep sack with a suitable tog-rating.
To vary the thickness of a swaddle blanket you can switch between muslin, the loose weave which is cooler, and jersey knit which is a closer, warmer knit, as well as double swaddle baby if necessary. For more detail check the Newborn sleepwear post.
#3 Newborn comfort for swaddling or sleep sacks
Anything next to baby’s delicate skin needs to be free from irritation. If you go for cotton or viscose rayon/rayon/rayon made from bamboo the fabric itself should be super soft and comfortable.
But look out for any seams, fabric folds in awkward places as well as velcro, zippers or any other fastening that could irritate. Obviously, this only applies to swaddle sleep sacks and sleep sacks, rather than swaddle blankets.
Have a good check inside these for any potential discomforts and keep an eye on all your baby’s sleepwear and day wear for seams/stitching coming loose.
#4 Sizing of swaddle blankets and sleep sacks for newborns, for safety & effectiveness
Swaddle blanket sizing
Go for a swaddle blanket at least 44 x 44 inch (111 cm x 111 cm) – 47 x 47 inches (120 cm x 120 cm) is the standard size.
Smaller than that are “receiving” blankets or burp cloths, at around 30 x 30 inches.
These smaller blankets will be big enough for a teeny tiny newborn but will quickly be outgrown and then will fail to keep those arms strapped in and snug. You’ll have an escape artist on your hands in minutes.
Sizing of swaddle sleep sacks or sleep sacks for newborns
Due to the fitted nature of a swaddle sleep sack, these are normally sized according to weight and/or length of your newborn (a downside of swaddle sleep sacks vs. swaddle blankets, as mentioned earlier). This can be a bit of a downside to swaddle sleep sacks, since one may only last a few weeks or so before you need to purchase the next size up.
Sleep sacks aren’t fitted so you’ll probably find one that’ll last the whole of the newborn phase.
For both types of sleep sack it’s important to choose the correct size for your baby, both for effectiveness and safety. As mentioned earlier, a sleep sack too small will be too tight and restrictive, not allowing for free movement of the legs and healthy hip development, too big risks SIDS if it rides up over baby’s head.
#5 Sleep sack or swaddling: ease of access for nighttime diaper changes
All standard sleep sacks and most hybrid swaddle sleep sacks all allow easy access to the diaper area so you can quickly and discreetly change diapers at night time.
Something to look for when choosing a sleep sack or swaddle sleep sack is to choose one that has double zippers so that you can unzip the bottom without completely exposing your baby. You might even be able to get away with not waking them up for a quick diaper check.
#6 Ability to easily transition out of the swaddle or swaddle sleep sack, into a regular sleep sack
Ideally, if you’ve been swaddling your newborn, you want to transition out of it gradually when the time comes (when baby starts to roll or turn full swaddling is no longer safe, as mentioned earlier).
So you want to be able to swaddle with one arm out for a few days and then with both arms out. This is possible with a swaddle blanket and most swaddle sleep sacks, so if you go for the latter, you may want to check.
My picks for the best swaddle blankets, sleep sacks and swaddle sleep sacks:
#1 Best swaddle blankets
Muslin swaddle blankets for newborns
All the following are at least 44 x 44 inch (111 cm x 111 cm), the recommended size for swaddling.
100% organic cotton muslin go for these ones from Burt’s Bees:
Or these ones from Aden Anais if you want to splash out on 100% viscose rayon.
Or for a combination of cotton and viscose rayon, these muslin swaddles from Upsimples offer good value.
Jersey knit newborn swaddles
The cheaper of the jersey knit options is this predominantly cotton one from Aden & Anais (95% cotton, 5% spandex)
If you want to go with 100% viscose rayon, you’ll pay a premium; this one from Posh Peanut is stunning though isn’t it?
Or for a budget viscose rayon option (it’s a blend of polyester and viscose rayon), why not try this newborn swaddle from Copper Pearl.
#2 Best sleep sacks for newborns
You can get baby sleeping bags with arms or ones without. If baby is wearing pajamas/sleepsuit/one-piece, the arms are covered. So buying a sleeping bag with arms shouldn’t be necessary unless it’s extremely cold at night.
If you live in a warm climate, a sleeping bag/sack without arms should be sufficient.
Baby sleeping bag with arms
A good option is this lightweight baby sleeping bag with arms from Hudson.
Baby sleeveless sleeping bag
And one without arms if you think your newborn will be plenty warm enough is this baby sleeping bag/sack/wearable blanket from Halo.
#3 Best hybrid swaddle sleep sacks
There are a huge variety of designs when it comes to the hybrid swaddle sleep sacks for newborns. The ones below are all quite different and you’re just not going to know what will suit your baby until you give one of them a go. It’s a bit pot luck.
Remember those key considerations when it comes to specifically choosing a swaddle sleep sack:
- sizing – will it grow with baby? Check the sizes available
- practicality/access for diaper changes – do you need to fully unwrap it for access to the diaper area?
- type of fastenings: velcro is easy but noisy so not ideal if you want to settle baby back to sleep quickly
- can you use it for swaddling baby with arms out, which makes transitioning out of the swaddle much easier
Budget-friendly, extremely effective and no noisy velcro, this newborn swaddle sleep sack from Miracle Blanket is well worth a go. A drawback is the inability to change diapers without fully unwrapping.
This swaddle sleep sack from Halo is a simple zippable sleeping bag with flaps or “wings” to secure the arms. It unzips from the bottom so you can easily change diapers without fully unswaddling and can be worn with the arms in a number of different positions, making for an easy transition out of the swaddle.
A downside is it’s fastened with velcro which could easily disturb a sleeping or easily startled newborn.
This swaddle sleep sack from Woombie couldn’t be any easier to put on: just pop baby in and zip. The two-way zip makes diaper changes a doddle and the armholes allow swaddling with the arms out, effectively converting it to a sleeping bag/sack.
This swaddle sleep sack from Love to Dream holds baby’s arms up, which some babies prefer. A big downside is it doesn’t grow with baby well – you’ll need at least 2 different sizes for the first 3 months.
When to stop swaddling a newborn
If you wondering when to transition from a swaddle to a sleep sack, it’s when your newborn starts to roll over from their back to their tummy. This usually happens around four months old for most babies.
When babies can roll over and are swaddled in a swaddle blanket or swaddle sleep sack, they could easily get stuck as with their face against the mattress since their arms are strapped in and unable to help them left their face up.
This poses a significant risk for suffocation. So if your baby starts rolling, you need to stop swaddling them. Normally by this point, the Moro reflex will have faded significantly, developing into the more adult startle reflex.
How to transition from swaddle to sleep sack
It’s likely that your baby will still enjoy and be very used to the close confines of the swaddle, so it’s best to stop swaddling gradually. Starting by swaddling with just 2 arm out for a day or 2, before removing the second – it’s perfectly OK to swaddle a newborn with arms out while transitioning out of the swaddle.
This way, your baby will still feel the tight hold of the swaddle, but with arms free will be able to roll back or at least lift her head having rolled onto her front.
Standard sleep sacks that act like wearable blankets, where baby’s arms are out and free to move, are safe for babies who can roll over so after a few days you with both arms out, you can start baby in a sleep sack, hopefully with no loss of sleep.
Conclusion: Still wondering whether to go for a swaddle or sleep sack for your newborn? Surely not!
Now that you have learned about the differences between sleep sacks, swaddles and hybrid swaddle sleep sacks and pros and cons of each, there should be no doubt in your mind that swaddling is the way to go. Swaddle blanket or swaddle sleep sack is more personal preference, either are effective, both for a newborn’s comfort and the sleep-related benefits.
Get baby swaddled and sleeping, so you can rest.