How long does the 4 month sleep regression last?

If you’ve suddenly found yourself with a baby who is waking frequently at night, struggling with naps, or just fussier than usual, you might be dealing with the infamous 4-month sleep regression. This phase can be exhausting and frustrating, leaving many parents wondering: how long will this last?

What is the 4-Month Sleep Regression?

At around 4 months of age, babies experience a permanent change in their sleep cycles. Unlike the newborn phase, where they drift in and out of deep sleep easily, they now develop more structured sleep cycles similar to adults—cycling between light and deep sleep more frequently (approximately every 2 hours during their night sleep). This shift means they wake up more often and may have trouble settling back to sleep on their own.

How Long Does The Four Month Sleep Regression Last?

The good news? The 4-month sleep regression can last between 2 to 6 weeks. However, the exact duration depends on several factors, including your baby’s temperament, sleep habits, and how you respond to their wakings.

Some babies adjust within a couple of weeks, while others may struggle for a longer period, especially if they develop or maintain sleep associations that make it harder for them to self-settle. If your little one has been rocked, fed, held to sleep, or relies on a pacifier, they may begin to expect that same comfort every time they wake during the night (every 2 hours). This can mean your baby will still be in the throes of the 4 month sleep regression for months to come. 

Sound exhausting? It is.

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Tips to Get Through It Faster

While you can’t avoid this regression entirely, there are ways to help your baby (and yourself) get through it more smoothly:

1. Encourage Independent Sleep Skills

   • Begin practicing drowsy-but-awake techniques before your baby hits the regression, to help your baby learn to settle independently.

   • Avoid creating strong sleep associations that rely on you, like rocking or feeding to sleep every time. If you are relying on these techniques, have a look at ways you can gently move towards more independent sleep for your little one. We can help you there!

2. Follow Age-Appropriate Awake Windows

   • At 4 months, babies typically handle at least 2 hours of awake time between naps. Keeping them up too long can lead to overtiredness, making sleep disruptions worse and conversely, trying to put them to bed too early can make sleep harder to achieve under any circumstances. In both scenarios you'll find yourself needing to more active and hands-on settling to get your baby to sleep, making the regression harder to manage.

3. Create a Consistent Sleep Routine

   • A predictable bedtime routine (e.g., bath, book, feed, bed) and a smaller naptime routine signals to your baby that sleep is coming and helps their body wind down.

4. Optimize the Sleep Environment

   • Keep the room very dark, use white noise, and ensure the temperature is comfortable to encourage restful sleep. Turn off all night lights, musical toys or mobiles that might distract and hinder your little one's ability to drift off.

5. Be Patient and Stay Consistent

   • Sleep regressions are tough, but they’re (usually) temporary. Know what you're dealing with, stick to a routine, be consistent with your approach, and remind yourself that this phase will pass.

When to Seek Help

If your baby’s sleep doesn’t improve after 6 weeks or continues to get worse, it may be helpful to seek professional guidance. Persistent sleep struggles can often be improved with gentle sleep strategies tailored to your baby’s needs - and that's where we come in. 

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The Takeaway

The 4-month sleep regression is a normal (but challenging) milestone in your baby’s development. While it can last 2 to 6 weeks, how you handle this period can make a big difference in how quickly your baby adapts. By encouraging good sleep habits now, you’ll set your little one up for better sleep in the months and years to come.

If you’re struggling, remember—you’re not alone! Many parents go through this, and there are gentle, effective ways to help your baby sleep better. Our Little Ones App is designed to guide you through sleep regressions and beyond, giving you the tools and support you need to navigate your baby’s sleep journey with confidence.