The 4-Month Sleep Regression: What is Happening and How to Survive It

Your baby is no longer a newborn. You think you’ve finally mastered some sort of sleep schedule—the first stretch of sleep is getting a little longer. And then, out of the blue…BAM! Suddenly, your baby’s naps last no more than 30-45 minutes, they wake up much more frequently at night (and I mean way more frequently—I’ll explain in a bit), and they become extra fussy in the evening. Throw in a growth spurt (hello, cluster feeding!), and it feels like you’ve hit the jackpot. Or, more accurately, you’ve hit the infamous 4-month sleep regression.

This is my current reality. I exclusively breastfeed—no bottles, no dummies, no pumping, no formula. Up until now, I’ve been getting up every 2-3 hours to nurse my son. But for the past couple of weeks, I’ve been waking up every hour to hour and a half. To put that into perspective, last night my baby woke up 11 times (yes, eleven!) overnight.

His daytime naps have also significantly decreased—he gets tired but fights sleep. This leads to overtiredness, fussiness, and, to top it off, a frustrating bedtime routine. He’ll do this false fall asleep trick, where he sleeps for about 15 minutes, wakes up again, and repeats this cycle three to four times before he actually falls asleep. And when he does, the first stretch lasts only about 1.5 hours. Needless to say, exhausted doesn’t even begin to describe how I feel. Zombie is probably a more accurate term—for both how I feel and how I look.

What Is the 4-Month Sleep Regression?

At around four months, your baby’s sleep patterns go through a massive developmental shift. Newborns spend a lot of time in deep sleep, but as they grow, their sleep cycles begin to resemble those of an adult—cycling through light and deep sleep more frequently. The result? More night wakings, shorter naps, and an overall disrupted routine.

Why Does It Happen?

Around 3 to 4 months, babies start producing their own melatonin—the hormone that regulates sleep-wake cycles. If you’re breastfeeding, your little one is also receiving melatonin through your milk, which helps support their sleep.

Up until now, your baby’s sleep hasn’t been strongly influenced by their circadian rhythm (our internal body clock that regulates sleep). However, as their sleep matures, they start experiencing more structured sleep cycles—similar to adults.

During this transition, babies wake briefly at the end of each sleep cycle. While these wake-ups can be challenging, they actually serve an important purpose: they allow your baby to briefly check their surroundings and ensure they are safe before drifting back to sleep.

Signs of the 4-Month Sleep Regression

• Trouble falling asleep at bedtime
• Shorter daytime naps and a significant decrease in total sleep
• Waking up much more frequently at night
• Increased fussiness and restlessness in the evening
• Crying more when waking up
• Needing to be held to sleep and waking immediately when placed in the cot

My son is experiencing all of these signs. I’ve read countless tips on how to survive this regression—everything from establishing a consistent bedtime routine, keeping the room dark and quiet, ensuring full daytime feeds, and tracking wake windows. And while I’m doing all of these (and more), nothing seems to be working just yet.

The Silver Lining

Instead of feeling discouraged, I choose to focus on the positives. My baby is growing, learning, and becoming more aware of the world around him. These sleepless nights? They’re just a small part of the beautiful journey of motherhood.

I cherish the extra cuddles, the midnight snuggles, and the little moments that make it all worthwhile.

If you’re going through this too, remember—you’re not alone! This phase will pass, and soon, we’ll look back and realize just how strong and resilient we were.

Hang in there, Mama—better sleep is just around the corner!

Have you experienced the 4-month sleep regression? What worked for you? Share in the comments below!