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Surviving the 4 month sleep 'regression'

Updated: Apr 2, 2022

Why has my baby stopped sleeping? What to do when your baby hits the 4 month sleep 'regression'.

By Alissa Pemberton. Midwife, IBCLC & Gentle Sleep Coach

As a parent you will almost certainly have heard the phrase 'sleep regression'. As an already sleep deprived parent these milestones become periods that you dread. We're just waiting for the other shoe to drop, feeling like we shouldn't get too attached to any good nights of sleep we get, because that next sleep regression will be just around the corner.

What is a sleep regression?

This phrase is used to refer to a period where a baby's sleep patterns suddenly change, and they may appear to 'regress' to waking more frequently overnight, having more disturbed sleeps and having difficulty napping for long periods of time. The phrase 'sleep regression' naturally has negative consequences. By definition a regression is a step backwards. So is our baby really taking a step backwards? Or is it a giant leap forward in their development that causes changes to their sleep.

Personally I like to use the term 'sleep transition'. This is really what it is. Our baby is transitioning from one way of sleeping, through a period of rapid development, to another way of sleeping. It doesn't have to be a negative experience, and with consistency and understanding you can help your baby to sail through these periods as easily as possible.

Why do sleep transitions occur?

There are a few key times in your baby's early years when they go through rapid periods of development, and significant changes to the way they sleep. Both of these things usually cause temporary disturbances to their sleep patterns.

At around 4 months your baby may be:

- beginning to roll

- tracking people across the room

- sitting with support

- holding onto rattles/toys

- reaching out for objects

Behind the scenes of all of these new skills is a little brain working in overdrive. The little electrical impulses which pass between cells in their brains are firing 24 hours a day, meaning it's much harder for your little one to shut down and settle into sleep. Imagine yourself with a nerve wracking interview or a big deadline the next day - every found yourself lying in bed, wide awake, with thoughts rushing through your head? This is similar to what's happening for your baby. They may need extra assistance and extra time winding down before bed to allow them to 'shut down'.

There is also a huge change happening in the way your baby sleeps around this time. At birth, babies only go through 3 stages of sleep - NREM3, NREM4 and REM (or light) sleep. Newborns go straight from being awake, into a deeper stage of sleep, and then into light sleep, to awake again. They start to transition to a pattern closer to that of an adult's sleep at around 4 months - where they fall asleep through lighter stages of NREM1 & 2, then into deep sleep, then into REM sleep. This means their sleep cycle is slightly longer, but their brain is also adjusting to a completely new way of falling asleep.

Falling asleep through these lighter sleep cycles also means they are more easily disturbed, and more likely to wake soon after being put down, or after a particular sleep trigger is taken away (like rocking, singing, white noise etc.) because they're still in a light sleep and much more aware of their surroundings.

From about 12 weeks your baby is also starting to develop their own circadian rhythm (or body clock) and their body has now begun to secrete melatonin in response to changes in light/dark to help them get to sleep. This means they are now much more likely to be affected by the environment around them when they're sleeping.

Your baby is also likely to be going through the 4 to 3 nap transition around this age and it's very possible during this period that their nap times may be out of sync, or nap lengths might not be right for your baby's needs - resulting in a baby who is overtired and sleep deprived, or a baby who is sleeping too late in the day and isn't tired enough come bedtime. Ideally around this age you should avoid your little one napping later than 4.30pm-5pm. If you can't fit the fourth nap in prior to this time, it might be time to consider dropping to three naps and bringing bedtime earlier to compensate.

What might you observe during a sleep transition?

When your baby is in this period between 3-5 months you'll most likely observe:

More frequent night waking This is common due to the developmental changes and changes in sleep pattern but may also be caused by - your baby being distracted during the day time and not feeding as well, therefore trying to compensate by taking more milk feeds overnight - being more susceptible to environmental changes like light in the room, being too hot/too cold, wriggling out of a swaddle or needing to be transitioned to a sleeping bag to maintain constant temperature, falling asleep with a certain stimulus such as white noise machines which switch off after a certain period of time, being held and put down asleep, falling asleep feeding, falling asleep with dummy etc. If your baby comes to the end of a sleep cycle, into a lighter sleep and that object/person/sound is no longer there, they are likely to wake fully rather than transitioning into another sleep cycle. - your baby having more difficulty napping in the day, particularly when surrounded by noise/light/activity even though they weren't troubled by this as a newborn - your baby needing more parental input to settle to sleep - your baby taking longer to wind down for sleep or becoming more easily overstimulated What can I do to ease this transition? If you're reading this and your baby hasn't yet hit the transition - great! You can start to put steps into place before hand, to smooth the road and help your baby slot back into their previous habits afterwards. If your baby is already there, never fear - you can still work to optimise your baby's sleep within the transition. It's worth understanding that making any dramatic changes to your baby's sleep or trying to implement a new routine or sleep program during a transition period might not be the most successful, I'll often advise parents to wait a few weeks and then try again. Firstly - be consistent. Try not to make drastic changes during a sleep transition. If you've established a previous rhythm which was working well for you, try to keep this consistent throughout the transition. This might include your bedtime routine, and settling methods. If need be, add in extra techniques or spend longer on the bedtime routine and wind down time before bed during this period. Ensure your baby is getting plenty of quality one on one time prior to bed, fill their 'love tank'! Try to remove excess stimulation in the hours before bed. Your baby is now starting to respond to changes in light and dark, and develop their own circadian rhythm. We can help this along by keep the environment in the house calm, quiet and as dark as possible in the hour or two before bed. Particularly in summer time in the northern hemisphere it's light well into the evenings so you might find that trying to close curtains/blinds, dim lights and create a calm quiet space for gentle play prior to bed helps to stimulate your baby's natural melatonin production - this hormone is vital for helping us to fall asleep. Understand your baby's sleep needs! Whilst it often gets blamed for everything, over tiredness can certainly have a role to play in disrupted sleep. If your baby is too tired prior to their naps/bedtime (or not tired enough) then we have an imbalance in what's called sleep pressure. Sleep pressure builds up the longer we are awake. In order for our little ones to fall asleep easily we need enough sleep pressure, but leave it too long and your little one will get a second wind of energy - caused by increases in cortisol and adrenaline (stress hormones). This will make them even more difficult to settle to sleep. In order to strike the right balance we need to know what's appropriate for your baby's age, and how long they can stay awake before they reach over tiredness. The table below is a rough guide, but I'd also encourage you to take some time to observe your baby and follow their cues. Eye rubbing, ear pulling, a glazed look in their eyes or avoiding eye contact and nuzzling their face into you/a blanket/a soft toy etc. are all sleep cues.

Most babies prior to 6 months don't have a need for specific 'sleep training' and although there are a number of programs which promise quick fixes, this is a period when your baby needs support and reliability from you. Methods such as cry-it-out promise a quick fix (and sometimes deliver) but this won’t be a positive experience for your or your baby. Your focus during this time should be adapting your routine to suit the changing needs of your baby, spending time getting to know your little ones patterns and sleep cues so you can be responsive to these, and focusing on ensuring your little one is getting adequate daytime sleep, and not staying awake too long between naps/bedtime. When it comes to naps, a nap anywhere is better than no nap at all. If, at present, your baby will only nap in the pram, carrier or in arms stick with this. Try to focus on getting them enough nap time during the day via the method that currently works best. Once they are through this tough developmental phase you can then work to help them in the transition to cot/crib. If you're having a particularly difficult time with your baby's sleep at any age it can pay to take some time out to focus on helping them. Try to postpone some activities for a week or two, take some quiet days for just being at home with your baby, where you can quickly respond to their sleep cues and where they're in just the right environment for sleep when they need it. Not trying to hold them off until you get to the car, or having to attempt to settle an overstimulated baby in the middle of a baby group or cafe. The best piece of advice you can receive as a parent is 'This too shall pass' and it couldn't be more true of these sleep transitions. Taking the time to understand the changes your baby is going through can help you navigate these bumps in the road with ease!

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