4 Month Sleep Regression Demystified!


As a child sleep coach, every day I talk about sleep regressions – the 4 month sleep regression in particular is a pretty popular topic!   I have countless Moms say “my son was sleeping 6 hours at nights at 3 months and then all of a sudden at 4 months, he began waking again every 2 hours all night – what gives?!”  Or “my daughter has never been a good sleeper, but it got even worse at 4 months.”

So, what happens at 4 months?

Around 4 months, babies go through a series of developmental changes and if baby hasn’t yet developed self-soothing skills, coupled with an age-appropriate schedule and environment, the 4 month sleep regression may be here to stay…

I know, I know – you don’t want to be one of those families whose child still doesn’t sleep at FOUR years old!  That’s why I’m going to help you understand what’s going on developmentally (it’s all really good stuff!) and give you tips on how to help your little one to get back to blissful sleeping!  That way, you can get back to your happy, shiny self vs. this walking zombie thing you’ve got going on now!  But first…

What is a sleep regression?

When a baby is sleeping well and then begins to wake frequently at night or begin to fight naps or refuse them, chances are your baby may have hit a sleep regression.  They can last a short while (a few days to a couple weeks) or your baby may never fully go back to their previous habits.  Sleep regressions typically occur around 4 month, 8 months and 18 months and coincide with standard timing for nap transitions. Around 4 months, babies transition from 4 naps to 3; around 8 months, babies transition from 3 naps to 2; and around 18 months, babies transition from 2 naps to 1.

Oftentimes, our babies are also working on major skills in each of these timeframes which can also play into the regression.  Sleep regressions are actually our babies are progressing!  They are maturing and developing, which is AMAZING, yet it can wreak major havoc on your baby’s slumber.

If your baby’s sleep needs have changed and you aren’t prepared to adjust their schedule to get those needs met, it can result in an overtired baby, which results in a downward spiral for both day and night sleep.

What is happening developmentally that causes the 4 month sleep regression?

  1. Baby sleep becomes more adult-like due to brain maturity: babies don’t immediately fall into a deeper sleep state when they fall asleep, like they did when they were newborns.  Now they begin to cycle between lighter and deeper sleep cycles, just like adults.  This is why the tricks you used to lull your baby to sleep don’t work anymore or take many, many attempts (think rocking/nursing to sleep) because they wake immediately when you put them down due to being in a lighter sleep state.  Continually repeating this cycle pushes bed / nap time later and results in less sleep and makes for an OVERTIRED baby <and a very frustrated parent!>
  2. Babies are beginning to roll, which makes using a swaddle no longer safe to use, but they still have the Moro startle reflex.  Many parents try to transition their babies out of the swaddle and into a sleep sack or just pajamas at this age, which causes them to startle themselves awake multiple times per night and at naps, resulting in an OVERTIRED baby.
  3. Baby’s sleep patterns mature and they usually begin waking earlier – standard, normal wake times are in between 6:00 – 7:00 am.   If your baby’s bedtime remains on the later side and they begin waking earlier, they won’t be meeting their nighttime sleep needs of around 11 hours per night.  This again results in an OVERTIRED baby.
  4. Your baby will begin to be ready to transition from 4 naps to 3 naps somewhere near the 4-month range and need around 4 hours of naps per day.  Instead of 4 shorter naps, babies should begin taking 3 longer naps to meet their daytime sleep needs.  If you baby hasn’t learned the skill of how to put sleep cycles together – sleep cycles are around 40 minutes at this age – it can result in not meeting daytime sleep needs and you guessed it…OVERTIRED once again.  This also plays into #3 above – with the three-nap schedule and to help ease through the transition, your baby will need an earlier bedtime while they adjust to their new schedule.
  5. Babies becoming increasingly more social – this means that they can no longer doze as well on the go.  Many parents want their babies to fit into their schedule and social life and unfortunately, that can backfire. If we aren’t meeting their biological needs on their schedule, it can result in frequent night wakings.  In addition, if we are trying unsuccessfully to have our baby take naps on the go that will further add to them accumulating a sleep debt and being OVERTIRED.

You may notice a common theme among all of the developments that your baby goes through relating to the 4 month sleep regression…they can all results in your baby becoming OVERTIRED.  Overtired babies wake more frequently at night and have more difficulty with napping during the day.

What can you do to help your baby move through the 4 month sleep regression with your sanity intact?

  • Identify your baby’s sleep associations and begin allowing your little one the opportunity to learn to sleep independently.  All of the things that we do to help our children sleep, actually prohibit them from learning to sleep independently and can actually become overstimulating for them. Associations include nursing / feeding to sleep, sucking, rocking, bouncing, walking, swinging and driving. <us, not them!>  It is incredibly important to put your baby down drowsy, but awake so they learn to fall asleep independently and put themselves back to sleep when they wake in the night.    Sometimes this can be easier said than done – let me know if you need support and help coming up with a customized, age appropriate plan to help.
  • Consider using a transitional swaddle when your baby begins to roll.  I really like the Zipadee-Zip and the Swaddle Up for babies around 4-5 months because it still gives the coziness of a swaddle/sleep sack, but also provides some help with the startle reflex.  Around 6 months plus, I recommend the Bitta Kidda Sleep Sack, which has a SAFE, built-in lovey and gives your baby freedom to move around their crib, while still keeping them cozy.
  • Move your baby’s bedtime earlier.  Most babies are ready for bed in between 6:00 – 8:00 pm or around 1.5 hours after the end of their third cat nap.  On especially rough naps days or a missed cat nap, don’t be afraid to move bedtime even earlier – they need to recoup that lost sleep in the beginning of the night.
  • Don’t let your baby get overtired.  At 4 months of age, babies can be awake around 1.25 – 1.75 hours before moving into an overtired state.  By keep their awake windows short, it makes it much easier for them to settle into their next sleep period.
  • Create the optimal sleep environment. If your baby hasn’t been spending much time in their crib, now is the time to introduce it. First, make sure your baby’s crib adheres to the AAP’s Safe Sleep Standards.  Start with naps to help them get accustomed to their new sleep environment.  Ensure that the room is cool (68-72), dark (my recommendations here) and has white noise, like the Marpac Dohm or Hushh running for all sleep periods.  Having a conducive sleep environment will go a long way towards helping your little one to snooze!

I hope this helps you to assist your little one in developing healthy sleep habits through the 4 month sleep regression.  This baby sleep stuff can be pretty confusing and if you need help, I’m always here.

For babies under 4 months, I offer 1-on-1 Newborn Sleep Seminars to help you get your little one on the right track and hopefully avoid the full 4 month sleep regression.

For babies four months and older, I provide customized plans, coaching and support to help you and your little one to get the rest you all so desperately need!

Schedule a no-cost 20-minute chat today so you can learn more about working with me.  Also, check out my reviews on Facebook!

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