Swaddle vs. Sleep Sack: Benefits, Drawbacks, Risks - Parents

Many parents turn to either swaddles or sleep sacks to keep their baby comfortable while sleeping. Swaddling also is used as a way to soothe a fussy newborn and promote sleep—especially as they adjust to life outside the womb.

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“Swaddling is a traditional practice of wrapping a baby gently in a light blanket in a way that mimics the womb,” says Jessica Morse, MD, a newborn medicine pediatrician at Children's Health and assistant professor at UT Southwestern Medical Center, adding that there are different types of swaddle blankets, including breathable muslin or cotton blankets.

A sleep sack, on the other hand, is an alternative to traditional swaddling and is a specially-designed baby garment for secure sleeping. But deciding which is best for your baby isn't always simple. For this reason, we spoke with pediatric experts to find out the benefits and risks of swaddles vs. sleep sacks and how to determine which is right for you. 

What Is a Swaddle?

Swaddling refers to snugly wrapping your baby’s arms near their chest to recreate the sensation they had in the womb, explains Stephanie Napolitano, MD, a neonatologist at Nationwide Children’s Hospital. “Swaddling your infant can help soothe them by giving them boundaries that they developed inside the birthing parent.”

Traditionally, swaddling is done with a blanket, says Dr. Napolitano. “However, when we swaddle with a blanket and leave infants unobserved during sleep, it can become loose and unwrap as the baby moves, and the loose blanket can create a suffocation risk for an infant.”

For this reason, pre-made swaddles or wearable blankets were developed to provide infants that containment but with blankets that will wrap and secure, generally with wings or straps and Velcro.

“A pre-made swaddle is generally more convenient than using a blanket that needs to be specially wrapped and folded, but both serve the same purpose,” adds Rebekah Diamond, MD, an assistant professor of pediatrics at Columbia University, and the author of Parent Like a Pediatrician. 

Pros and Cons of Using a Swaddle

Swaddling an infant provides that tactile feedback needed to soothe or calm them in the safest way during sleep, says Dr. Napolitano. That said, there are some drawbacks to using a swaddle as well. Here’s an overview of the pros and cons of swaddling.

Benefits of Swaddling

• Provides tactile feedback
• Can be soothing and calming
• Creates sensation of being in the womb
• Promotes sleep

Drawbacks of Swaddling

• Can pose challenges in trying to wake your baby from a deeper sleep
• Increases risk of overheating
• May interfere with breastfeeding if baby sleeps too long
• Can be difficult to use correctly

Safety Considerations for Using a Swaddle

Typically, it’s recommended that you stop swaddling your baby when they show signs of being ready to roll over. Generally, this occurs around 3 to 4 months of age or older—though every infant is different.

“Once this is the case, babies should never be swaddled with their arms inside,” says Dr. Diamond. “Swaddles can still be used after this age if both of the baby's arms are free."

When you are using a swaddle, also make sure that the swaddle isn’t near your baby’s face or too tight around their chest or hips, adds Dr. Napolitano. “[Their] hips should have ample space to move and develop.”

There also is some evidence that swaddling may make it more challenging for babies to wake from a deeper sleep. And, while this extended snoozing may be attractive for sleep-deprived parents, this can interfere with breastfeeding and nutrition, as well as increase the risk of sudden infant death syndrome (SIDS). There also is a risk of overheating–especially if you notice damp hair, flushed cheeks, or even a heat rash.

You can reduce the risk of overheating by dressing your baby appropriately, says Dr. Napolitano. “A good rule of thumb is generally what you’re comfortable wearing, plus one layer.”

What Is a Sleep Sack?

A sleep sack is similar to a swaddle, but much less restrictive, explains Robert Quillin, MD, a board-certified pediatrician and medical director at Pediatrix Medical Group. “Sleep sacks have unrestricted arm movement, which can be sleeved or sleeveless [and] the lower portion is looser and allows your baby to move their legs more freely.”

Sleep sacks also don’t have the same ability to wrap tightly around a baby's torso and arms but instead has a pouch-like shape that babies can be zipped into, says Dr. Diamond. "A blanket or any loose cloth is unsafe for infant sleep, so sleep sacks replace blankets for added warmth and comfort."

Pros and Cons of Using a Sleep Sack

Because blankets pose a risk of suffocation for babies younger than 24 months, a sleep sack is a safer option, says Maria Lopez, a sleep expert and director of Sleep Sense en Espanol. “A sleep sack also keeps your child warm all night.” 

Here are some of the benefits and drawbacks of using a sleep sack:

Benefits of Using a Sleep Sack

• Can be used even when your baby can roll
• Safe for newborns
• May be easier to use than a swaddle

Drawbacks of Using a Sleep Sack

• Comes in limited sizes
• May not be useful or safe once a baby can stand or becomes mobile
  

Safety Considerations When Using a Sleep Sack

According to Dr. Quillin, the same safety considerations that apply to a swaddle also apply to a sleep sack. “The weight or thickness of the blanket may really be the only potential safety concern when used correctly.” 

That said, when you choose a sleep sack, make sure that it's roomy enough for free movement, especially if your child can sit or stand up, says Lopez. “As with swaddles, do not use weighted sleep sacks, and avoid overdressing your child when using one. Make sure the fabric is appropriate for the weather to prevent overheating.”

How to Decide Between a Swaddle or Sleep Sack 

Choosing between a swaddle and a sleep sack when your baby is under 3 to 4 months of age—and they’re not yet rolling over—really comes down to personal preference and your goals. 

If you have a fussy baby who needs comfort and security during naps, you may want to swaddle them from time to time. But if your baby enjoys moving their arms and kicking their legs—even if they can’t roll over—they may prefer a sleep sack.

The weather and temperature of the room also should be considered. Swaddling in a warm room or during hot weather may cause your baby to overheat due to the restrictive nature of the swaddle. In these situations, a lightweight sleep sack might be a better option for nighttime sleeping—as long as you don’t overdress them.

Ultimately, though, Lopez recommends using age as the primary decision maker. “I do not recommend swaddling babies over 4 months, regardless of whether or not they have learned to roll over.” 

Learn the Purpose, Usage & Benefits of Sleep Sacks for Babies

Good sleep is essential for everyone, especially baby, as it helps with brain and body development, overall health, and of course, mood. With so much information out there about getting a good night’s sleep, it’s important to understand what products might help your little one fall asleep, and stay asleep, because chances are, if baby sleeps well, so will you! 

Enter the sleep sack! Sleep sacks are pretty much a staple on every parents ‘must have’ list, but what is a sleep sack, you ask? Sleep sacks are a popular bedtime option for parents when their little one outgrows swaddling. Essentially a wearable, zippered blanket for baby, sleep sacks mimic swaddling, which helps baby sleep better for longer periods of time. See below for more frequently asked Qs:

What is the purpose of a sleep sack for babies?

The purpose of a sleep sack for babies is multi-faceted, but mainly, sleep sacks help your little one stay warm and comfortable, which translates to better sleep for all of you!

Want more information on Swaddle Sleeping Bags For Babies? Feel free to contact us.

What do sleep sacks do?

Sleep sacks help regulate your infant’s body temperature which keeps them from being too cold, too hot, and makes their sleep just right! A sleep sack also eliminates the need for extra blankets in their crib, co-sleeper, or bassinet, which  helps keep baby’s sleep-space safe.

Do sleep sacks help babies sleep?

In a word, they should… okay, that’s two words! Of course, every baby is different, but Dreamland Baby weighted sleep sacks work for infants who like the sensation of being touched. Weighted sleep sacks are good for baby because they help them feel secure and “held” - like a hug - which can also help calm a fussy baby.

Keep in mind, weighted sleep sacks are considered safe as long as the weight of the sleep sack is no more than 10% of your baby’s body weight. So a 10-pound baby should wear a sleep sack weighing no more than one pound. A 20- pound baby should wear a sleep sack no more than 2 pounds, and so on.

What are the benefits of a sleep sack for babies?

Now that  you know what’s a sleep sack, you may be wondering what are sleep sacks good for? The benefits are many. Sleep sacks work because they help regulate baby’s body temperature creating a comfortable night (or naptime) sleep. They also eliminate the need for extra blankets in baby’s sleep-space (which is always a safe choice). Dreamland Baby weighted sleep sacks offers our unique features of evenly distributed weight from shoulders to toes which helps baby feel calm, fall asleep faster, & stay asleep longer. 

Why do sleep sacks work for babies?

Sleep sacks work because they keep your infant safe, warm, and comfortable so they can fall asleep faster and stay asleep longer.  

What are baby sleep sacks used for and how do I know if my baby needs one?

 A sleep sack is like a wearable blanket for your infant. They help regulate body temperature providing a warm and comfortable slumber. Sleep sacks are a safe way for baby to catch some Zzz’s by eliminating the need for blankets in their sleep space. If your baby prefers to sleep “arms up” and/or doesn’t quite come around to the sleep swaddle, it may be time to consider a sleep sack.  

When should a baby use a sleep sack?

Sleep sacks are good for newborns through toddlerhood, although every baby is different. Using your sleep sack for nighttime and naptime also helps establish a pattern and becomes a familiar “sleep time” routine.

How to choose a sleep sack for babies?

There are plenty of sleep sack options out there from colors and patterns to sizes… but of course, we’re partial to our Dreamland Baby weighted sleep sack. Ours has a detachable swaddle wing so it can be used as either a swaddle or a sleep sack. It is designed to help your baby feel calm, fall asleep faster and stay asleep longer. The gentle weight naturally reduces stress and increases relaxation through deep-pressure stimulation to give your baby feelings of security and comfort. 

What is the best sleep sack to buy for babies?

The best sleep sacks to buy for baby are 100% cotton, provide room for baby to kick and move their legs. We may be biased but our favorite sleep sack for babies is our Dreamland Baby weighted sleep sack that baby can use starting at 8lbs through toddlerhood. They are  designed to help baby feel calm, fall asleep faster and stay asleep longer. The gentle weight naturally reduces stress and increases relaxation through deep-pressure stimulation to give baby feelings of security and comfort - like a hug! This deep-touch pressure can help soothe anxiety and encourage calming sleep.  We also have a two-way zipper for easy diaper changes making middle of the night changes easy so everyone gets back to sleep faster.

How does a sleep sack work?

A sleep sack is like a sleep bag, but for babies. It keeps them snug, warm, and safe all night long, thus promoting safe and healthy sleep. Its fit is important. Your baby should not be able to remove the sleep sack. The idea is that a sleep sack keeps your baby warm, cozy, and asleep all night long since it won’t fall off like a blanket does.

Sleep sacks function as a wearable blanket that zips up and has openings for your baby’s head and arms. Just like a swaddle blanket, a sleep sack gives your little one the comforting experience of a gentle, warm hug. However, unlike a swaddle, sleep sacks give your baby the freedom of being able to move their arms.

Swaddling becomes unsafe once your baby begins to roll over, leaving many parents searching for a safe alternative to using a blanket. Sleep sacks help babies transition from being completely swaddled at night to eventually sleeping with a blanket when it is safe to do so. With a sleep sack, your baby’s legs will still be somewhat contained, which can help prevent them from trying to climb out of their crib in the middle of the night.

While some parents choose to use a sleep sack from the beginning, others will swaddle and then transition to a sleep sack. For a smooth transition, try Dreamland's patent-pending Weighted Transition Swaddle designed to help your baby safely transition to arms-out sleep with a sleep sack. Our sleep sack features 3/4 length weighted arms help reduce the Moro (startle) reflex while also providing your little one with range of motion. With this swaddle, your baby can safely roll over, allowing them to get used to sleeping with their arms out and get ready for the next stage of safe sleep products.

What is a sleep sack made out of?

Sleep sacks come in a variety of materials, but typically are made from lightweight cotton, linen, or muslin for maximum breathability and comfort. You may also find sleep sacks made from synthetic blends such as polyester or rayon. Cotton is the most durable and suitable for infants with sensitive skin.

Depending on the season and your local climate, you may need a thicker sleep sack with long sleeves, typically made with fleece or wool. These materials will help your baby stay cozy and warm even in the coldest weather, without the need for layering several blankets.

Do sleep sacks have different sizes?

In order to accommodate your growing little one, sleep sacks are available in several different sizes ranging from newborn to extra large for toddlers. Our bestselling Dream Weighted Sleep Sack is available in 4 different sizes ranging from 0-6 months to 24-36 months.

In addition to coming in different sizes, sleep sacks may come with long sleeves or be sleeveless to accommodate different sleeping environments and temperatures.

What is a weighted sleep sack?

A weighted sleep sack functions just like a regular sleep sack with the benefit of deep pressure stimulation. Weighted sleep sacks provide additional comfort and security designed to help your baby fall asleep faster and stay asleep longer. Your little one can do everything they would do in a non-weighted sleep sack including roll over, sit, and even stand up.

It’s important to note that weighted sleep sacks are safe as long as they are within the recommended weight limits. 

What are the advantages of weighted sleep sacks?

While both sleep sacks and weighted sleep sacks help provide better sleep for your little one, there are some added advantages of using a weighted sleep sack.

Once your little one starts rolling over on their own or breaking free of the swaddle, swaddling is no longer considered safe. This is where sleep sacks and weighted sleep sacks come in. If your baby is missing the restriction and comfort that comes with swaddling, a weighted sleep sack can provide a safe alternative for your baby. Weighted sleep sacks help your baby feel safe and secure during the night, reducing anxiety and promoting a sense of calm. They can help your baby begin to develop healthy sleep patterns and positive sleep associations.

In fact, NICU studies have proven that weighted blankets help babies sleep more calmly than non-weighted blankets.

In addition, Dreamland Baby weighted sleep sacks have been designated as “hip-healthy” by the International Hip Dysplasia Institute. The advantages don’t stop there…sleep sacks and weighted sleep sacks also have the benefit of helping your little one regulate their body temperature while they are asleep. All of these perks make sleep sacks and weighted sleep sacks a must-have item for new parents.

Is a sleep sack the same as a wearable blanket?

A sleep sack is also commonly referred to as a wearable blanket or a blanket sleeper. They are essentially bodysuits made of the same material as a blanket with an opening for your child's head as well as their arms. If your child truly enjoys sleeping with a sleep sack rather than a blanket, you should be able to find wearable blankets for children and even adults for sale.

When do babies outgrow sleep sacks?

Sleep sacks can be safely used from birth until they no longer fit properly. Depending on your child’s height and weight, they will probably begin to outgrow their sleep sack around the age of 2 or 3. Most larger sleep sacks will accommodate toddlers up to 30 pounds / 40 inches tall.

Sleep sacks are designed to help you create a healthy sleep environment for your baby until they have reached the recommended age to sleep with loose blankets. It's suggested that all soft bedding be kept out of your child’s crib until they are at least 12 months old.

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