4-Month Sleep Regression

The 4 Month Sleep Regression (or Progression!)

So, your little angel who slept like a teenager for the first three months of their life is now sleeping like a baby – aka, waking up every few hours and popping their eyes open at the drop of a pen, or the click of the door as you leave the room? While many would call this shift a sleep regression, experts say it’s more like a sleep progression, showing that your baby is properly developing, physically, cognitively, and emotionally.

But, even though your long nights spent with your eyes wide-open babe indicate positive progress, it can also wreak havoc on your sanity and health. Instead of just grin and bearing through many months of sleepless nights, understanding the factors that impact baby’s sleep as they develop will allow you to make adjustments that enhance their (and your) ability to catch some zzzs.

Here are the most common shifts occurring in your child’s world around their four-month birthday, and how to work with them so they don’t siphon away all your slumber:

4 Month Sleep Regression: Heightened Curiosity

While your baby spends the first few months of life getting used to not being in a cozy in-utero suite, they’re now ready to start taking in and enjoying their surroundings. This heightened curiosity, which is brought about by baby’s ability to begin using their primary senses (hearing, vision, taste, and touch), causes them to be much more sensitive to where they can and cannot fall asleep.

While your baby might have had no trouble falling asleep in the grocery store, car, movie theater, or other stimulating environments in those first few months, they now have FOMO (fear or missing out) and have little interest in snoozing when they can be checking out all the interesting colors, lights, sounds, tastes, and movements around them.

To prevent this heightened curiosity from putting up a block between your baby and sweet sleep, put more planning into your baby’s sleep schedule. Start paying attention to the common times throughout the day your baby seems to be sleepy and adjust your schedule to ensure you can have them in a quiet (or white noise filled), cool, comfortable, and dark space during those times. Minimizing the amount of stimulation baby has during their down time will up their chances of drifting into dream world, instead of powering through sleepy times and ending up fussy and fatigued.

4 Month Sleep Regression: Sensitivity to Change

Newborns are pretty adaptable to change, as long as they’re with you, but as they become more aware they become more sensitive to situations like travel, a new home, different people, or even a shift in the composition of breast milk if your diet changes.

If you notice your baby’s sleep habits beginning to shift, think about changes that have happened in their world and how to make the necessary adjustments to help them ease back into being a successful sleeper. For example, if you’ve just been on a trip where a time change occurred, you can try to get them back to an optimal bedtime by adjusting the time you begin their nighttime routine by thirty minute increments (either earlier or later, depending on what direction you traveled).

4 Month Sleep Regression: Enhanced Motor Skills

Babies become more dexterous around 4 months and are able to do more with their hands, like shake a rattle, grab a stuffed animal (or your hair!), or even roll over. Because these new abilities can tire baby out, use them to your advantage by providing plenty of safe opportunities for baby to explore their new abilities. Pay attention to your baby’s sleep signals (like rubbing their eyes, yawning, becoming fussy, or anything else you notice they do when they’re getting tired) as they play and transition them to their sleepy space when they show these signs.

4 Month Sleep Regression: Ability to Self-Soothe

Around four months of age babies become more apt at being able to learn to soothe themselves back to sleep. 80% of children wake at night, but many parents wouldn’t even know it because their child has the ability to drift back into sleep without assistance. Because self-soothing is a learned skill, allow your baby to hone this ability by giving them some time and space to fall back asleep, which they might do with the assistance of a self-soothing technique like sucking on their hand, for example. Use your judgment when it comes to how much time you want to give baby before you go in and support them in the soothing process – trust your instincts.

It’s also important to know that it’s common for babies to whimper and moan, or fall into strange breathing patterns, when in REM (rapid eye movement) sleep. And occasionally, the sounds and movements that can accompany REM sleep, or the transitions into or out of it, might trick you into thinking your babe is awake. So, when it sounds like baby is up and at ‘em take a few beats before you rush to soothe them, because it’s very possible that they may slip back sleep.

4 Month Sleep Regression: Be Gentle With Yourself

First and foremost, you’re likely a mombie (mommy zombie) if you’re moving through the four-month sleep regression with your baby and deserve to rest as often as you’re able. Stick to the “sleep when baby sleeps” motto, so popular in the first few weeks of baby’s life, regardless of how much laundry, emails, or dishes you have.

In addition, know that sleep tips and tricks can only do so much and work in varying degrees of success with each child. So, if you’ve tried everything and your baby still refuses to sleep more than 30-minutes at a time, don’t label yourself as a “bad parent” and know that if you keep working at it there will come a time when you and baby get a blessed five straight hours of sleep.

Parenting is a wild ride of rapids, rowing up stream, and getting tossed from your boat, but find solace in knowing that there will be times when it turns into a lazy river that will let you drift into gentle dreams with your baby by your side.

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Natalie Barnett, PhD serves as VP of Clinical Research at Nanit. Natalie initiated sleep research collaborations at Nanit and in her current role, Natalie oversees collaborations with researchers at hospitals and universities around the world who use the Nanit camera to better understand pediatric sleep and leads the internal sleep and development research programs at Nanit. Natalie holds a Ph.D. in Genetics from the University of New England in Australia and a Postgraduate Certificate in Pediatric Sleep Science from the University of Western Australia. Natalie was an Assistant Professor in the Neurogenetics Unit at NYU School of Medicine prior to joining Nanit. Natalie is also the voice of Nanit's science-backed, personalized sleep tips delivered to users throughout their baby's first few years.

Kristy Ojala is Nanit’s Digital Content Director. She spends way too much time looking at maps and weather forecasts and pictures of Devon Rex cats and no-cook dinners. A former sleep champion, she strives to share trustworthy somnabulism tips with other parents—praying for that one fine day when no tiny humans wake her up while it’s still dark out. Her kids highly recommend 3 books, approximately 600 stuffies, Chopin’s “Nocturnes,” and the Nanit Sound + Light for bedtime success.

Mackenzie Sangster is on the Brand and Community team at Nanit. She supports content development and editing for Nanit’s Parent Confidently blog as well as other marketing initiatives. Outside of work, she enjoys spending time with her friends, cooking, being active, and using the Pro + Flex Duo to keep an eye on her fur-baby, Poppy!

Holly Hays is a contributor and writer for Nanit, channeling her years as a mama and former magazine editor to create fun, useful content for fellow busy, trying-to-do-their-best parents and caregivers. Holly has written for a wide range of brands and media outlets (Ergobaby, HGTV, Manhattan Toy Company, OXO), loves to cook and read mystery novels, and leans heavily on her two daughters to keep her up to date on all the latest slang.