Is your baby going through the 4 month sleep regression? Learn why this sleep regression happens and follow these 5 tips to get rid of it.

The 4-month sleep regression is usually one of the first sleep regressions new parents encounter. It doesn’t help that you’re finally starting to adjust to life as a new parent and your baby is finally getting acquainted to living outside of the womb.
Your baby may have been sleeping well up until this point. You might have thought you sailed past all those newborn sleep horror stories you heard and then the four-month regression hits. Suddenly your 4-month old starts experiencing sleep problems, which means no one is sleeping well.
The 4-month sleep regression often comes from out of nowhere and can turn a new parent’s nights and life upside down.
Keep reading for tips on getting rid of the 4 month sleep regression and get your sleep back!
Why the 4-Month Old Sleep Regression Happens
Unlike the 6 month sleep regression, 9-month sleep regression or 12-month sleep regression, this is a sleep regression that actually makes sense, scientifically speaking. (Though that doesn’t make it any easier to handle).
Your baby has come a long way since the newborn days. Even though your baby’s life is still so new, they have already gone through so many developmental changes these last four months.
Babies’ sleep cycles change around four-months old and become similar to our sleep cycles as adults. Your newborn slept really hard, which is why she probably slept through bright lights and loud noises for the first three months.
But around the four-month-mark, your baby’s sleep patterns change. And the 4-month regression can really start between 3.5 to 5 months of age.
We all wake up several times throughout the night, going in and out of different sleep stages. But we put ourselves back to sleep easily and unknowingly when we see our familiar bed, pillow, blanket, etc.
We don’t even realize it happens because we naturally connect sleep cycles and are able to come out of one sleep cycle in a light sleep and and go seamlessly into deep sleep into the next sleep cycle.

The four-month sleep regression comes in as babies start to change from a newborn-like sleep cycle to an adult-like cycle. Couple that with the fact that your baby is learning new skills and hitting developmental milestones like rolling over in sleep and babies can really start to have a difficult time with sleep!
If your baby is rocked or fed to sleep, then it can be very strange for them to wake up in the middle of the night and be in a completely different environment than the one they fell asleep in. They may wakeup looking for your familiar arms or chest that helped them fall asleep initially.
It would be like if you fell asleep on a friend’s couch and then woke up in the middle of the night in their bathtub. Super weird, right?
As babies are rocked or nursed to sleep each time, they may start to wake up looking for the same sleep associations that helped them get to sleep in the first place.
They start to need this same sleep prop every time they come out of one sleep cycle in order to go into a new sleep cycle—which is about every 40 minutes.
A newborn waking up every 45 minutes or so is what makes the four-month sleep regression so hard for parents who are dealing with it. This creates scattered sleep and very long nights for the whole family in the middle of a four-month regression.

What are the Signs of the 4 Month Sleep Regression?
Babies are so complicated! Sometimes it’s hard to tell if they’re going through a growth spurt, developmental milestone, need their wake windows adjusted, or are dealing with a sleep regression.
The 4-month sleep regression is one of the easier sleep regressions to pinpoint though. (Although it’s not the easiest one to deal with!)
Here are some signs your baby may have hit the dreaded 4-month sleep regression:
- Your baby is between 3.5 and 5 months old. ( Yes, your baby can have the 4 month sleep regression at 5 months old. Four months is just a range in this case).
- Your baby was sleeping well but is suddenly having more frequent night wakings.
- Your baby is having a harder time going back to sleep after a middle-of-the-night feed.
- Your baby starts having a difficult time falling asleep at bedtime or for naps.
- Your baby takes short naps and starts waking up 30 to 45 minutes into her nap.

How Long Does the 4 Month Sleep Regression Last?
Most sleep regressions last anywhere from two to six weeks. The four-month sleep regression can come on suddenly and out of nowhere.
While other sleep regressions may stop just as soon as they began, the 4-month sleep regression is different, because your baby’s sleep has gone through a permanent change.
As the 4-month sleep regression hits, how you respond will determine how long it lasts.
If you start new sleep associations like feeding your baby to sleep, then that will become your baby’s new normal.
If you rock or nurse your baby to sleep every time that she wakes up, then that will quickly become something she needs and you may have a hard time doing anything different. Learn how to stop nursing your baby to sleep.
If you work on helping your baby self-soothe, then the 4 month sleep regression usually takes about 2 to 4 weeks to fully pass.

Learn how to stop nursing to sleep and teach independent sleep habits with The Baby Dream System, my sleep training course designed for babies 4 months through 2.5 years old. You’ll learn how to teach your baby to sleep independently, wean night feeds, and encourage longer naps and night sleep. Learn more here.
What Happens after the Four-Month Sleep Regression?
This will really depend on how you and your partner respond when your baby wakes up during the four-month sleep regression. If your baby gets used to being fed, held, or rocked to sleep, then they will most likely need those same things to get back to sleep each time they wake up.
Introducing new sleep props out of desperation can affect your child’s sleep for many months to come.
Make sure to keep your baby from getting overtired and try putting her down awake so she learns independent sleep skills.
If you stay consistent with the tips below in our sleep regression solution section, then the regression will exit just as quickly as it entered.

How Do I Get Rid of the 4 Month Sleep Regression?
So what are tired parents to do if their baby is struggling with the 4-month sleep regression?
Follow these tips for a 4 month sleep regression solution and to kick it to the curb.
1. Check Wake Windows and Baby’s Sleep Schedule
If you haven’t already, now is a great time to start your baby on a consistent sleep schedule. Follow 4-month old wake windows and a consistent 4-month sleep schedule.
Your 4-month old can stay awake for about 1.5 to 2 hours in between naps and needs between 3 to 4 naps each day with about 12 hours of night time sleep.
2. Have A Consistent Bedtime Routine
Baby’s can start to recognize routines early on. Establishing your baby’s bedtime routine will help cue to their brain that sleep is coming and help prepare them for sleep.
Following the same series of events each night can really help. We recommend feeding, diaper change, pajamas, books, and bedtime.
3. Create A Conducive Sleep Environment
Use white noise and blackout curtains to help optimize your baby’s sleep. Many babies are ready to drop the swaddle and transition to a sleep sack around this age as well.

4. Awake, Not Drowsy
Your baby’s sleep has changed. Start putting your baby down fully awake.
Drowsiness is the first step to falling asleep so it’s important that your baby doesn’t get help getting to drowsy.
Try to separate feedings from sleep by 30 minutes and put your baby down fully awake so she can enter drowsiness on her own.
5. Sleep Train
You can use a sleep training method to help your 4-month old start falling asleep on their own.
Methods like the Chair Method or Pick Up Put Down can work well for this age and allows you to stay in the room while your baby falls asleep.
The 4-month sleep regression isn’t a myth, but not all babies experience it.
I have worked with many families whose babies were in the middle of the four-month sleep regression and it was ROUGH! Those families will attest that it is a very real thing.
Sometimes you can do everything right, and it just takes time for your baby to kick the regression. Continue to stay consistent and it will pass.
Try to take turns with your partner and know that it will be over soon enough.
If you need help getting through the four-month sleep regression and are ready to start getting longer stretches of sleep, check out The Baby D.R.E.A.M. System.
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