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    The Best Sleep Sack for Newborns? One That Prevents Your Baby's Arms From Wiggling Free

    Your baby craves that snug holding and that's exactly what swaddling will give her.

    Dr. Harvey Karp

    Written by

    Dr. Harvey Karp

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    baby breaks out of snoo sack swaddle

    ON THIS PAGE

    • Best Sleep Sack for Newborns
    • Benefits of Using Newborn Sleep Sacks for Swaddling
    • How to Keep Your Baby Snug With the Best Newborn Sleep Sack
    • More Newborn Swaddling Tips

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    Best Sleep Sack for Newborns

    Some babies calm immediately with swaddling, but many resist and may actually cry louder initially. But remember, your little one had very little free space to move around in the womb. She actually craves that feeling of snug holding she had for 9 months, and that is exactly what swaddling will give her. Once you get your baby swaddled securely and start the other 5 S’s, she should calm quickly and stay calmer longer (and sleep longer) when swaddled. 

    One of the best ways to swaddle your baby is to use a swaddle sack.

    Benefits of Using Newborn Sleep Sacks for Swaddling

    Using a newborn swaddle sack makes it way easier to swaddle your baby. Rather than dealing with blankets of all sizes and shapes, and worrying about using the right tucks and folds, you just place your baby in the swaddle sack, and voila! 

    Here, we show you how, using our SNOO Sack. (You can use these steps with any swaddler. Just make sure you never allow your baby to sleep with any loose blankets.) 

    How to Keep Your Baby Snug With the Best Newborn Sleep Sack

    First, you want to lay your baby down on a folded thin blanket or cloth nappy, with the SNOO Sack laid beneath her (unzipped). Your baby's shoulders should be about 5cm higher than the top of the SNOO Sack. 

    Then, fold one side of the blanket over your baby's arm and underneath her body.

    Repeat on the other side.

    Now, you have both of your baby's arms secured by the blanket/cloth nappy. Pull SNOO Sack's inner arm bands across your baby's chest, keeping her arms straight at her sides. Make sure the band is attached snugly. Bring the lower flap between the baby's legs and attach it to the inner band. 

    Pull the sack up and over the feet and shoulders and zip the sack completely closed...top and bottom. Note: The top of the zipper should be positioned well below the chin. Your baby is now snugly in her sack and ready to be placed in her SNOO...and calmed to sleep!

    You can watch a video of this technique below!

    More Newborn Swaddling Tips

    Any time you swaddle (and especially when you add layers) be sure to check your baby’s ears: If they are red and hot or if your baby's neck is sweaty…then your baby is too warm. Cool the room or dress her more lightly.

    At 4 to 5 months, parents can try letting an arm or two out of the large SNOO Sack through the arm hole. If the baby starts waking more (hits herself in the face with her newly freed arm), you will want to put her arms back in the SNOO Sack for another 1 to 2 weeks and try again. This gradual process of freeing her up will help her make an easy transition to the cot at 6 months. SNOO's Weaning feature helps with that too!

    Happy swaddling!

    Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider. Breastmilk is the best source of nutrition for babies. It is important that, in preparation for and during breastfeeding, mothers eat a healthy, balanced diet. Combined breast- and bottle-feeding in the first weeks of life may reduce the supply of a mother's breastmilk and reversing the decision not to breastfeed is difficult. If you do decide to use infant formula, you should follow instructions carefully.

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