Parents hear a lot about when and how to stop swaddling, but what comes next?
I’ve seen many moms and dads make understandable mistakes when first approaching the mystery that is baby bedtime attire. When it comes to dressing a tiny tot for sleepy time, the goal of the first four months is the exact opposite of what lies beyond — and that can make for a certain amount of pajama confusion.
Newborns have very immature nervous systems, lots of reflexive movements, and little control over their limbs. Swaddling keeps them nestled tightly while their nervous systems are developing and gives them the best chance of sailing smoothly in and out of stages of sleep.
The nervous system matures quickly, though, and once a baby is somewhere between three and six months, they are much more likely to regulate movements, have good control over their arms and legs, and have a mature circadian system (internal clock) telling them to sleep when it’s nighttime.
At this point, it’s time to dress a baby for movement, which means pajamas that are fitted, not too heavy, and that don’t get tangled easily (my co-author and I always recommend one-piece pajamas instead of sleep sacks or other sleep suits for this reason).
Expect and encourage your baby to tumble around, sit up, stand up, and eventually walk around and explore their crib; it’s their domain and they should feel free to move unencumbered.
At first, babies can be disoriented by the free-range movement, but over time it does help them sleep. That’s because our babies are more likely to sleep through the night when they choose their own body position, and when they have the freedom to replicate that position easily every time they stir.
One of the most common missteps we see in sleep consultations is people overdressing their babies. There’s a misconception that warmer equals sleepier, but the opposite tends to be true: people of all ages sleep best when the room is cool (65-68 degrees). Imagine yourself in a very warm room with heavy layers on you neck-to-toe … it’s more stressful than anything.
Here’s a guideline for how to dress baby for cool, but comfortable sleep:
If it’s chilly: Layer a onesie under your child’s footie pajamas. If it’s very cold, add a layer of a blanket sleeper (a fleece zipper pajama that goes over the thin cotton pajama).
If it’s warm: Opt for just a one-piece breathable cotton pajama. You can dress your baby in footie pajamas, or one-piece pajamas with no feet. If it’s very warm in the middle of the summer, just a onesie will do. As adults, we’re used to being covered to sleep, but just like using a pillow, babies don’t know the difference and don’t mind having toes or legs exposed.
When bedtime rolls around, think cool and free to move. Your baby will have the best chance of finding their cozy position and having a good night’s sleep.
Heather Turgeon is a psychotherapist and co-author of The Happy Sleeper: The Science-Backed Guide to Helping Your Baby Get a Good Night’s Sleep—Newborn to School Age (Penguin Random House).