The 4 Month Sleep Regression Doesn't Exist!

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4 month regression


There's no such thing as the 4 month regression

You may have heard of sleep regressions before but the 4 month regression can't really be  described as a regression but rather a permanent change in how your baby sleeps.

Happening anytime between  2 - 6 months of age this regression marks the maturation of your baby’s sleep cycles from baby ones to more adult like sleep cycles.

So what happens?

Before the ‘regression’ . When your baby first fell asleep they fell into REM sleep first, (rem means rapid eye movement and this is the state of sleep when we often dream)

Then cycle into  NREM sleep (known as Non REM  stage 3/4 sleep) and transition/cycle between the two throughout their sleep.

When the sleep cycle matures to that of a more adult like sleep cycle. Instead of falling asleep and entering into rem sleep first, baby now drifts into light sleep known as NREM sleep 1 / 2 then into deep sleep stage NREM sleep 3 / 4 and then into REM sleep lastly resembling a more adult like sleep cycle, unfortunately although  sleep cycles are now more adult like…. This change does not lengthen the sleep cycles significantly ( sorry if your were hoping for a lie in soon).

This change in the way your baby’s sleep cycles through varying depths can feel different & many babies can struggle with the transition between sleep stages. Often waking and needing help to get back to sleep overnight and sometimes at nap times too.

Hence the ‘regression’ or disruption to sleep.


How to survive this change in sleep for your baby

Not every baby experiences a disruption in sleep, however these changes to your baby's sleep cycles are unavoidable, but there are some things you can do to minimise sleep disruption if your baby finds adjusting to these changes challenging.


Avoid Overtiredness.

Overtiredness tends to make sleep worse causing frequent night waking and early morning waking too (read more about overtiredness and its impact here), structure your babies daytime naps to avoid overtiredness but don’t let your baby nap too much that they are undertired at bedtime and aren’t ready to sleep. Get help with structuring naps and total nap times here


More patience may  be needed.

Your little one may struggle to transition between sleep cycles and wake up more often needing help toThe 4 Month Sleep Regression Doesnt Really Exist! get back to sleep. Nap times and overnight sleep may become more challenging as your baby wakes more often and may need your help to get back to sleep where they perhaps didn't need help before. Many mums worry about creating ‘bad’ habits by doing this but IMHO if your baby was previously sleeping well and settling without help before, helping them quickly get back to sleep in the short term preserves sleep rather than making it worse. Leaving your baby to cry to sleep instead of supporting them can potentially damage the connection/attachment between you as these changes to sleep can feel different and what worked to get them sleeping before ( leaving them to settle on their own because they could) may not work now due to these changes but it's all temporary, I find responding quickly to them to calm them and soothe them back to sleep is best. Now is not the time to sleep train. Your baby may also become more cranky, more clingy and may cry much more often during the day as well as at night. You may have to give your baby a lot more attention than you already are and many mums can be left feeling drained or touched out. If you can allow your partner and other family members to support you or share the care and comforting of your little one.


Keep Your routines in place.

As i said before, avoid overtiredness as much as possible by structuring naps, but also keep your routines in place. Stick to your daily routines  s much as possible. Keep your bedtime routine in place as well as your pre nap ritual and your daily routines etc. This is a time of rapid development for your baby which can seem very unsettling. Sticking to your daily routines provides a familiar anchor to a day that has had many variables and changes to their development in it. The 4th and 5th month of a babies life involves rapid development and that can be a unsettling for your baby, keeping familiar routines in place is one of the things that can help your baby feel more secure in a period of lots of change.


Overnight hunger may increase

During periods of rapid brain growth and development your little one may become hungrier even overnight.  They may wake up and seem hungry where before they’d perhaps not woken for feeds in a while. This rapid growth requires more energy and glucose  basically making baby hungrier. Many mums worry that giving a bottle or feeding again overnight is encouraging bad habits, but i disagree. Hungry babies may find it difficult to settle to  sleep ( i know i can’t sleep if i’m hungry) so i often advise mums who worry about night feeding again to work from a don’t offer, don’t refuse” stand point.

If you can settle baby back to sleep without a feed then great, go with it. But if it's obvious that your baby is hungry and won’t settle then refusing a feed is unfair. It’s better to feed, calm and settle them back to sleep.


Don't struggle by yourself, join me and a community of mums who want to lovingly get their little ones sleeping through the night sooner rather than later.

To access my FB group, the sleep schedules for 0-12 months or anything else baby sleep check out the links on my linktree here