Understanding the 4 Month Sleep Regression: Essential Guide for Parents
There is no shortage of sleep regressions; you conquer one, only to plunge straight into the next. In the first 2 years alone, your baby will go through:
4 month sleep regression
8 months sleep regression
12 month sleep regressions
18 month sleep regression
2 year sleep regression
While they may be frustrating, sleep regressions are times of huge developmental leaps as your baby works through crucial cognitive and/or physical changes. Disrupted sleep often coincides with significant milestones because the formation of new connections in your baby’s brain and nervous system can destabilize sleep.
During the 4 month sleep regression, your baby is busy mastering rolling and flipping over, but there is also something even BIGGER happening inside of your baby that makes this regression unique among all the others.
What exactly is the 4 month sleep regression?
At birth, babies lack a circadian rhythm, the natural sunlight driven sleep-wake cycle that all children and adults have. It’s one of the reasons that we feel sleepy at night and alert during the day. Newborns are born with no circadian rhythm: they have chaotic sleep patterns with no distinction between night and day and do not have the biological capability to feel sleepy at night and alert during the day.
The 4 month sleep regression signals the maturation of your baby’s circadian rhythm and the transition from newborn to adult sleep patterns. A newborn’s sleep cycle is immature and is composed of only two stages of sleep: REM (Rapid Eye Movement) Sleep and Non-REM sleep. After this sleep regression, their sleep cycle will be made up of four distinct stages:
The Good:
This is a huge milestone in your baby’s life! This shift in sleep patterns means your baby will now be more wakeful during the day and capable of more predictable sleeping patterns at night. Many parents will start to notice night wakings at specific times of the night as baby’s newly established 45-60 minute sleep cycle mature.
The Bad:
A newborn spends 50% of their sleep in REM aka “active sleep” and 50% in Non-REM aka “quiet sleep”. They are able to quickly cycle between these two stages making it easier for them to fall and stay asleep for longer stretches. In contrast, the 4 stage sleep cycle involves baby waking up at the conclusion of every 45-60 minute sleep cycle. This is totally normal and everybody does it! As adults we are so used to putting ourselves back to sleep during the night that most of the time we don’t even notice these wake ups.
A baby who is experiencing this for the first time and who has little or no experience putting themselves back to sleep is going to struggle. This is why at the end of every sleep cycle, your baby is going to call for you in order to be rocked, nursed, or soothed in some way back to sleep.
The Ugly:
Unlike the other sleep regressions that come and go when a baby has worked their way through the latest development, the effects of the 4 month sleep regression will not simply pass.
Your baby either learns how to go back to sleep by themselves or they will continue to rely on you to help them back to sleep.
Expect cat naps that last the length of a single sleep cycle to become the norm until your baby learns to independently join sleep cycles.
Do all babies experience the 4 month sleep regression?
Yes, all babies will go through this biological shift, BUT not all babies will show outward signs of sleep regression. Babies with solid sleep foundations are better equipped to navigate this period with minimal disruption.
Download the free Newborn Sleep Roadmap in order to establish healthy sleep foundations from the start.
Signs of the 4 month sleep regression?
A few off days don’t necessarily signal a regression, but if your baby is 3-4 months old and you start to see these with more frequencies, you can be pretty confident that you have entered the regression:
Frequent night wakings
Short naps (less than 1 hour)
Taking a long time to fall asleep (more than 20 minutes)
Baby only wants to be held to sleep
Increased fussiness
How long does the 4 month sleep regression last?
The change in your baby’s sleep cycles won’t happen overnight, but gradually over a period of time. The 4 months sleep regression, however, can either slowly sneak up on you or turn things upside down in a matter of days. The regression itself lasts two to six weeks, but if your baby does not learn to sleep independently during this time, expect the sleep disturbances to continue for weeks or months afterwards.
Steps to manage the 4 month sleep regression?
If you have not yet implemented healthy sleep foundations for your baby, now is the time to start. Focus on the following:
A strong sleep foundation is the base for all healthy sleep habits.
1. Ensure Adequate Daytime Nutrition:
It’s not uncommon for babies to increase their night time caloric intake during the 4 month sleep regression, which in time can lead to genuine hunger wakings at night.
Focus on full daytime feeds every 2-3 hours for babies under 4 months, and every 2.5-3.5 hours for babies over 4 months.
If you are nursing or bottle feeding your baby back to sleep, try alternate soothing methods such as rocking, bouncing, and or shushing and patting.
2. Optimized Sleep Environment:
As babies now rouse fully between sleep cycles, environmental disturbances will play a bigger role in your baby’s sleep quality. Use black out shades to keep the room dark, and maintain the temperature between 20-22°C (68-72°F). If you can’t control the temperature make sure your baby is dressed appropriately. Keep a white sound machine running the whole nap/night.
Download the free visual guide on how to dress your baby in different temperatures.
3. Consistent Nap & Bedtime Routine:
Babies thrive on predictability: a consistent routine before nap or bedtime signals to them that sleep is coming and gives them the opportunity to wind down their mind and body.
Aim for a 30-45 minute routine before bed, and a condensed version at nap time. Move nursing/bottle to the beginning of the routine so that baby does not rely on it to fall asleep every time.
4. Fine Tune Wake Windows:
A baby who is going into nap or bedtime overtired, will have a much more difficult time falling and staying asleep. Don’t miss their optimal sleep time by following age-appropriate wake windows while also paying attention to your baby’s sleepy cues. If you’re already following wake windows, it may be time to lengthen the windows as baby’s ability to stay awake longer improves.
If you don’t know what your baby’s wake windows should be, download the free Optimal Newborn to Preschool Sleep Chart.
Pay attention and learn your baby’s unique sleepy cues.
5. Provide Lots of Floor Time:
In addition to their changing sleep cycle, babies are also going through big cognitive and physical developments at this time. Give your baby ample floor time to practice their rolling and flipping over, or else they may choose to practice (and get stuck on their belly!) during the night instead. Floor time is also an opportunity for your baby to be active and build good sleep pressure for better sleep.
6. Sleep Training:
Many babies will need formal sleep training in order to help them master the skill of independent sleep. There is a wide range of strategies that you can use, from very high parental involvement to “cry it out” extinction method. While all of these methods will work if done correctly and if sleep foundations are in place, some babies (and parents) are better suited to certain strategies. Make sure that your baby is at least 4 months adjusted age before sleep training.
If your baby’s sleep has you feeling overwhelmed, hang in there, you are not alone! Many parents, myself included, have been where you are, and I promise that you will not be stuck there forever.
If you are looking for guidance and support, I specialize in helping babies overcome the 4 month regression and restoring healthy sleep patterns. No “cry it out” methods, only a supportive and carefully customized approach that is best suited for your baby.
Discover what the Complete Sleep Solutions Infant Program has to offer and schedule your free 15 minute sleep assessment call today. A friendly voice and good night sleep is nearby!
