swaddles and babies

Swaddles, and transitional sleep sacks, and sleep sacks, oh my…

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Swaddles, transitional sleep suits, and sleep sacks – when and why you should use them

For some reason, swaddles always seem to be one of the most overwhelming parts of infant sleep. If you’re a parent (new or seasoned), you’ve surely found yourself wondering – why are there so many different options? What is the difference between a swaddle, a transitional sleep suit, and a sleep sack? When am I supposed to be using each one?

Well, I am here to answer all of those questions for you, so let’s get started!


A swaddle is what your baby will use from the day of their birth until they begin to show signs of rolling. A swaddle is a blanket that wraps your baby up like a tiny burrito to limit their limbs from moving.

The moro reflex and swaddles

All babies are born with a reflex known as the Moro reflex. The Moro reflex, also known as the “startle reflex,” is responsible for the involuntary jerky motions of newborns. These jerky movements can be enough to wake your infant up, even during their deepest stage of sleep. Swaddles are used to help muffle those reflexes and prevent them from unintentionally waking themselves up.

Swaddles are also beneficial in recreating the restrictive environment of the womb and decreasesing external stimuli. In the first few weeks of life, swaddles are also a great tool for helping to calm a fussy baby.

 Swaddle recommendations

For the first 1-2 weeks of life, usually something like the Swaddle Me swaddles are enough. These swaddles are easy to use and cheap. Until baby gets a little stronger, theses swaddles are also hard for them to escape.

swaddling a baby

Unfortunately, this phase doesn’t last long. Before you know it, your newborn baby is a master at Houdini-ing out of the swaddle. At this point, I typically recommend transitioning to something with a little more reinforcement, like the Miracle Blanket Swaddle. This product uses baby’s own body weight to hold down their arms, which makes it harder for them to escape. These are really the only 1-2 products you need until your baby starts to show signs of rolling. Rolling typically occurs somewhere between 10-16 weeks.

Once your baby begins rolling, they need access to their arms (in case they roll in the crib). At this point you have 2 options: you can start using a transitional sleep suit or a sleep sack. The age at which you make this transition will help you decide.


I typically recommend transitional sleep suits for those who transition out of the swaddle early. Remember that startle reflex we discussed in the last section? Well, that reflex will disappear on its own around 4-5 months. But until then, we’ll need to prevent those jerky motions from waking them up. Transitional sleep suits are designed to allow baby access to their arms, should they need it, but include a structured element to help continue muffling that startle reflex.

Sleep suit recommendations

magic merlin swaddle

The transitional sleep suits I recommend are the Merlin’s Magic Sleep Suit or Swaddle Sleeves Swaddle (SNOOZECLUES for a 10% discount).

The Merlin’s Magic sleep suit uses padding to keep baby’s limb’s relatively still throughout the night. You do not need to transition out of the Merlin until baby is able to roll over while wearing the suit or completely loses their startle reflex.

The Swaddle Sleeves swaddle is probably a better bang for your buck. It uses padded sleeves to help muffle the startle reflex. Once your child is ready, the sleeves can be removed and the remaining suit can be used as a regular sleep sack . This prevents the need to buy yet another sleep item as your child grows!


Sleep sacks should be used once your child’s startle reflex completely disappears, which is usually around 4-5 months. If you transition out of the swaddle on the later side (the startle reflex is gone), you may consider moving right to a sleep sack and skipping a transitional sleep suit.

Think of sleep sacks as a wearable blanket. The main purpose of a sleep sack is to keep your child warm while it is still contraindicated to have loose blankets in the crib. Your child does not have to use a sleep sack. There is no physical benefit to a sleep sack. However, it can serve as a great sleepy cue for the brain.

Sleep sack recommendations

baby in a kyte baby sleep sack

Kyte baby sleep sacks are my favorite. These sleep sacks are so soft and are manufactured using a breathable bamboo material that helps regulate baby’s body temperature.

For daycare and as backups I usually suggest the Halo sleep sacks since they are relatively inexpensive and come in a variety of sizes, fabrics, and thermal grades.


I recommend keeping your child in a sleep sack until they transition to a big kid bed (or as long as they will let you). The reason why I recommend this is two-fold. First of all, blankets are pretty ineffective for toddlers. They will usually kick them off before they even fall asleep and they aren’t really coordinated enough to put them back on. Secondly, sleep suits serve as a great hack for making it more difficult for kids to climb out of the crib, which can help to extend the amount of time spent in the crib! 😉


So there you have it… you don’t need to spend a million dollars on swaddles, sleep sacks, etc. There is no need to get fancy or buy the latest and greatest product on the market. The swaddle or sleep suit should be used to help baby achieve a restful night of sleep, while supporting their developmental needs. Don’t overthink it!

You can find most all of the products I discussed in this post in different patterns and togs on my Amazon Store.

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I'm Kristen

The expert & woman behind the screen. I'm also your new best friend who is ready to empower you on this incredible journey.

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