Skip to Content

Surviving the Four-Month Sleep Regression

Learn all about the dreaded four-month sleep regression, including what to expect, tips for surviving it, and how to avoid the four-month regression in the first place!

four month sleep regression - baby fighting sleep

The four-month sleep regression is usually the first sleep regression parents encounter. It doesn’t help that you’re finally starting to adjust to life as a new mom or dad 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 BOOM, the four-month regression hits and your 4-month old won’t sleep anymore.

The 4-month sleep regression comes from out of nowhere and can turn a new parent’s nights and life upside down.

Why the Four-Month Old Sleep Regression Happens

Unlike the 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!).

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 four-months old your baby’s sleep patterns change. And the 4-month sleep regression can really hit between 3.5 to 5 months.

Everyone—babies, toddlers, adults, you, me—wakes up several times throughout the night, but we put ourselves back to sleep easily and unknowingly when we see our 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 and go seamlessly into the next.

The four-month sleep regression comes in as babies start to change from a newborn-like sleep cycle to an adult-like cycle.

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! They may wonder where are those arms that held me or that nipple that was in my mouth as I fell into a slumber?

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 association 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 the next—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.

four month old baby

How Long Does the Four Month Sleep Regression Last?

Most sleep regressions last anywhere from two to six weeks. The four-month sleep regression can come on suddenly and seemingly from out of nowhere. While other sleep regressions may leave just as soon as they began, the four-month sleep regression is different.

As the four-month sleep regression hits, how you respond will determine if your baby picks up new sleep habits that can turn the four-month regression into the new norm in your household.

If you rock or nurse your baby to sleep every time that she wakes up, then that will quickly become something she needs for the next several months of her life. Learn how to stop nursing your baby to sleep.

Baby DREAM System mockup

Learn how to stop nursing to sleep and teach independent sleep habits with The Baby Dream System, my sleep guide 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 are the Signs of the Four 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 times adjusted, or are dealing with a sleep regression.

The four-month sleep regression is one of the easier sleep regressions to pinpoint though. (Although it’s not the easiest one to deal with!) and can affect both naps and night time sleep,

Here are some signs your baby may be hitting the dreaded four-month sleep regression:

  • Your baby is between 3.5 and 5 months old. ( Yes, it can start early. Four months really means a range in this case).
  • Your baby was sleeping seemingly well and has suddenly started waking up multiple times in the middle of the night.
  • Your baby is having a harder time going back to sleep after a night feed.
  • Your baby starts waking up 30 to 45 minutes into her nap.
baby dealing with four month sleep regression

What Happens after the Four-Month Sleep Regression?

This will really depend on how you and your partner handle your baby’s wakeups 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.

baby with dad

Four-Month Sleep Regression Solution

So what are tired parents to do if their baby is struggling with the four-month sleep regression? Well, you have a few options, depending on what habits you’ve already setup with baby sleep.

If you haven’t already, now is a great time to start your baby on a consistent sleep schedule. Start teaching her how to fall asleep independently so she learns to come out of one sleep cycle and into the next.

You can do this through using an eat play sleep routine and following an appropriate four-month sleep schedule. (Check out my example sample 4 month old schedule.) Four months is also the earliest that you can sleep train if you want to break previously used habits like rocking or nursing to sleep.

If you’ve already established an eat play sleep routine and your baby is falling asleep independently, then keep at! You may need to start putting your baby down awake now, instead of doing drowsy but awake.

Also, make sure you’re following an appropriate wake time for 4 month old.

ebook ad for tired parents

If you’ve setup independent sleep habits from an early age, your baby may not hit the regression at all. I was so nervous to enter four months. We had been diligent about getting on a good sleep routine and our girl breezed past it!

That early work we had done really paid off!

The four-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, drink plenty of coffee and wine and remember that it will be over soon enough!

If you need help getting through the four-month sleep regression, feel free to reach out! I can come up with a customized plan that works for your family to get your baby sleeping!

Amy Motroni