You've been patting yourself on the back. Your baby was sleeping in 3-4 hour stretches. You were finally feeling human again.

And then, out of nowhere, everything falls apart.

Welcome to the 4-month sleep regression. It's real, it's exhausting, and you're not imagining it.

What Is Sleep Regression?

Around 4 months (sometimes 3, sometimes 5), babies go through a massive developmental leap. Their brains are basically rewiring.

What changes:

  • Sleep cycles mature from newborn patterns to adult-like patterns
  • They become more aware of their surroundings
  • They start learning to roll, grab, and explore
  • Their circadian rhythm is developing

    • Translation: Their sleep goes from "pretty good" to "what is sleep?"

    Signs You're In It

  • Waking up every 1-2 hours (or more)
  • Taking shorter naps
  • Fighting bedtime like it's their job
  • Needing MORE help to fall asleep
  • Being fussier than usual
  • Wanting to play at 2am (WHY?!)

    • Sound familiar? Yeah, you're in it.

    How Long Does It Last?

    The good news: It's temporary. The bad news: 2-6 weeks is the average.

    I know. I KNOW. That feels like forever when you're running on 2 hours of sleep.

    But it WILL end. I promise.

    What's Actually Happening

    Your baby isn't broken. They're not regressing. They're actually making HUGE developmental leaps.

    Their brain is learning to:

  • Connect sleep cycles
  • Process more information
  • Understand object permanence (you exist even when they can't see you!)
  • Control their body better

    • It's exhausting for them too. Imagine learning to use a new operating system while also learning to flip your body over.

    Survival Strategies That Actually Help

    1. Create a Strong Sleep Environment

    This is where my white noise machine became my best friend.

    Block out light, keep the room cool (68-72°F), and make it BORING. No mobiles, no music, just sleep vibes.

    2. Stick to Your Routine

    Even if it's not "working," keep doing your bedtime routine. Consistency helps signal "this is sleep time" even when their brain is going haywire.

    Our routine:

  • Bath (when we have energy)
  • Pajamas
  • Feed
  • White noise on
  • Dark room
  • Cuddles and down

Takes 20 minutes, does it most nights.

3. Practice Naps

Daytime sleep affects nighttime sleep. I know naps are a battle right now, but try to protect at least one good nap a day.

Even if you have to hold the baby or use the stroller—whatever works.

4. Watch Wake Windows

At 4 months, babies can usually handle 1.5-2 hours awake before needing sleep again.

If they're awake too long: overtired = harder to sleep If they're not awake long enough: not tired enough

It's a delicate balance, and you'll probably mess it up (I did). That's okay.

5. Don't Start Bad Habits (Unless You Want To)

Everyone will tell you "don't create bad habits!"

But here's the truth: Do what you need to do to survive.

If that means rocking to sleep? Rock. If that means co-sleeping safely? Do it. If that means letting your partner take over? YES.

You can "fix" habits later. Right now, you need sleep.

What DOESN'T Help

Sleep training at 4 months: Most experts say wait until at least 5-6 months. This regression is neurological—sleep training won't fix it.

Cereal in the bottle: This is a myth. Sleep regression isn't about hunger.

Skipping naps to "tire them out": This backfires HARD. Overtired babies sleep WORSE.

Comparing to other babies: Your friend's baby sleeping through the night? Good for them. Doesn't help you.

My Story

With my first, the 4-month regression hit at 3.5 months and lasted 5 weeks. FIVE WEEKS.

I cried in the shower. I ate cereal for dinner. I Googled "is this normal" at 3am more times than I can count.

With my second, I knew what was coming. I was prepared. It still sucked, but at least I knew it would end.

And it did. Both times.

Real Talk: Take Care of Yourself

This is the part no one tells you: YOU need to survive this too.

Tag team with your partner: Take shifts. Even one 3-hour block of uninterrupted sleep helps.

Lower your expectations: Nothing else matters right now except sleep.

Ask for help: Can someone watch the baby for an hour so you can nap? DO IT.

Say no to everything: This is survival mode. You don't need to host playdates or meal prep or have a clean house.

It Gets Better

I know you don't believe me right now. But it does.

One day (soon!), you'll realize your baby slept a longer stretch. Then another. Then you'll wake up in a panic thinking something's wrong because it's been 6 hours.

This regression ends. And when it does, sleep often improves BEYOND where it was before.

You've Got This

You're in the trenches right now. You're exhausted. You're Googling at 2am (hi!). You're wondering if you broke your baby.

You didn't. Your baby is developing exactly as they should.

And you're doing an amazing job, even when it doesn't feel like it.

Hang in there, mama. This too shall pass. ☁️