Sleep Sack Vs. Swaddle: Which One Is Right For Your Baby

sleep sack vs. swaddle

There are so many questions about sleep for your baby, and one of the biggest ones may be when to use a sleep sack vs. swaddle.

In this article, we’ll look at the benefits of sleep sacks and swaddles, their differences, and when to use each to help you make an informed decision for your little one.

Table Of Contents

What Is A Sleep Sack?

sleep sack vs. swaddle


Sleep sacks are like cozy bodysuits made of a blanket-like material with a hole for your baby’s head and two holes for their arms.

Also called wearable blankets or blanket sleepers, these loose-fitting “sacks” allow your little one to move their legs appropriately while helping them feel secure.

Because sleep sacks don’t restrict arm movement, they are perfect for when your baby starts rolling and getting more mobile in their crib. The sleep sack moves with them and doesn’t get tangled up, ensuring a more comfortable sleep experience for your little one.

In addition, a sleep sack typically comes with zippers, velcro, snaps, or some combination of the three. For example, the Newton Baby Sleep Sack for Babies has an inverted zipper for easy diaper changes during the night.

Sleep sacks are also a safer alternative to a loose blanket in the crib and can aid in the prevention of SIDS.

The American Association of Pediatrics outlines additional safe sleep guidelines, such as keeping the crib space empty with no loose objects, blankets, pillows, or toys. Only a tight-fitted sheet is approved.

That means a sleep sack could be just what you need to keep your little one safe and cozy!

How Long Can Babies Use Sleep Sacks?

When it comes to deciding on a sleep sack vs. swaddle, it’s important to note that babies can generally get more use out of sleep sacks. That’s because swaddles become unsafe once infants start to roll over.

Rolling over typically happens around four months, but the perfect time to switch into a sleep sack from a swaddle will vary from baby to baby.

Each little one develops at a different rate. And as your baby learns new skills, they will be testing them out in their beds (rolling over, crawling, pulling up).

Once you switch your baby into a sleep sack, watch for any signs of discomfort as they grow. Eventually, their legs will feel confined, and the discomfort may cause them to have trouble falling or staying asleep.

In addition, when your little one is able to get out of their crib or bed on their own, a sleep sack can make it hard and unsafe to walk. These are some great indications that it’s time to transition out of the sleep sack.

At this point, your child may be ready for a loose blanket. The AAP recommends that your little one not use a loose blanket until they are at least one year old. Otherwise, your baby is safe to wear a sleep sack as long as they want to and as long as they can fit in one.

What Is A Swaddle?

A swaddle may sound a little more familiar to you than a sleep sack. That’s because many prenatal classes teach swaddling techniques, and it is likely the first thing you will put your baby in after they’re born.

Swaddling has been around for 4,000 to 4,500 years. But in the modern age, it became popular during the early 1990s after the promotion of back sleeping for all babies.

Swaddling involves wrapping your newborn in a blanket so they feel comfortably snug with only their head outside of the blanket. It helps soothe your baby’s startle reflex, also known as the Moro reflex, which is when your baby suddenly flails their arms and legs.

The Moro reflex is a normal reflex an infant has when they are startled by a loud noise or movement. This can jolt them enough to wake them from their sleep. It can occur anytime up to six months of age.

Baby in a swaddle

While swaddling can help your little one fall right back to sleep when this reflex occurs, as soon as they show signs that they are learning to roll over or they can already roll over, stop swaddling and consider a sleep sack instead.

How To Swaddle

Some parents are overwhelmed at the sight of a swaddle, but it’s easy once you get the hang of it. Here’s what you’ll do:

  1. Lay the swaddle on a safe, flat surface in a diamond shape with the top corner folded down four to six inches for baby’s head.
  2. Lay baby down on their back in the center of the swaddle with shoulders touching the top of the folded corner.
  3. Gently hold baby’s left arm by their side with the hand near chest level and, at the same time, pull the swaddle up and over her left arm and snugly tuck under baby’s right side.
  4. Pull the bottom corner up and tuck it into the fold across baby. Wrap the opposite corner all the way around the front, middle, and back of your baby and tuck it into the little pocket you’ve created on the front

Remember, practice makes perfect!

Sleep Sack Vs. Swaddle For Newborns

When it comes down to deciding whether to use a swaddle vs. sleep sack for your newborn, consider which will comfort your baby the most.

During the first few weeks of life, a swaddle helps ease your little one’s transition from the womb. The tight, cozy hug your baby receives from a swaddle mimics the comfort they are used to. For this reason, many parents choose to swaddle their newborns.

But, remember, once your little one grows out of the newborn stage and starts to roll over or show signs of rolling over, a sleep sack is the safer choice.

Safe Swaddling And Sleep Sack Tips

No matter which option you choose, you want to make sure your baby is safe. To help ensure your baby is out of harm’s way, here are six important tips to keep in mind.

Mom learning sleep sack vs. swaddle for the baby

1) Consider Your Baby's Temperature And Environment

Regularly check your little one’s temperature, and make sure that they are wearing weather-appropriate clothing. A good rule of thumb is to dress them in one layer more than you’re comfortably wearing.

Also, refrain from swaddling your baby if they are sick or have a fever. If they are sick, dress them in a single light layer of clothing.

2) Use Thin Materials

Another way to control your little one’s temperature is to use a small cotton sheet or muslin square as your swaddle.

Don’t place any additional material on top of a swaddled baby or a baby using a sleep sack. For example, a blanket could cause them to overheat.

3) Do Not Swaddle Above Their Shoulders

Ensure any material is secure and won't come loose as your baby moves. The swaddle or sleep sack should never cover their neck or head.

Covering a baby's neck can increase their risk of overheating and prevent proper breathing. Also, make sure not to wrap it too tightly or cover their nose or mouth.

5) Always Put Your Baby To Sleep On Their Back

This bears repeating: Never put your baby to sleep on their front or side, no matter what they’re wearing. Always place them on their back.

Placing your baby on their back to sleep — or in the supine position — significantly lowers SIDS risk and ensures that your little one is sleeping as safely as possible.

6) Adhere To Safety Standards

Both sleep sacks and swaddles should fit appropriately. Follow the instructions on age and weight, and consider using a lower TOG rating to minimize overheating risks.

7) Make Sure Caregivers Practice Swaddle Vs. Sleep Sack Safety

Parents need a break now and then. Whether a grandparent, sibling, or babysitter is stepping in for a few hours or a few days, take the time to explain safe swaddling and sleep sack practices.

The Right Choice For Your Baby’s Comfort And Safety

Baby in sleep sack

Now that you are familiar with the differences between a sleep sack vs. swaddle, you are ready to decide which one is right for your little one. But rest assured that both are designed to help your baby feel calm, fall asleep faster, and stay asleep longer.

Newton Baby is here to help with our limited edition Sleep Sack For Babies and our Newton Baby Organic Swaddles, which can double as a light blanket when your little one reaches one year old.

Whichever one you choose, it’ll be sweet dreams for your precious angel!

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