Just when many of us finally feel we are getting some predictability with sleeping patterns…. BANG! Along comes the Four Month Sleep Regression! In Wonder Weeks terms, this also equates to Mental Leap 4: Events (which starts between 14.5-19.5 weeks). If you are going through this, you may find some comfort in knowing that this developmental leap is Universal. Frustration, exhaustion, tears, rocking in the foetal position, sleep deprivation, and screaming profanities is considered normal.

So what’s going on?

  • More difficulty falling asleep and staying asleep – despite our best efforts of rocking, feeding, carrying, or keeping to a routine (spending 1.5 hrs to get your baby to sleep, only to have him sleep for 15-20 minutes… then attempting for 20 minutes to re-settle him back to sleep to no avail, can be very frustrating!)
  • Lots of drooling, fists in mouth
  • General crying, fussiness and irritability during the day
  • Heightened clinginess, and obvious signs of distress when mum is out of sight, or if left with anyone else but mum!
  • Fussy on the breast or bottle (almost too distracted to feed during the day)
  • Change in appetite; either more or less hungry
  • Increased restlessness overnight (e.g. squirming, crying out)
  • More frequent night wakings due to an increased need to feed; most likely making up for distracted feeding during the day


At four months of age, our baby’s sleep patterns change from ‘newborn’ to ‘baby’  (i.e. more distinct cycles of REM/active sleep and Non-REM/deep sleep – similar to adults). This change can be unsettling for our babies as they learn to adjust to their new sleep cycle.
At this age, our babies are increasingly alert and aware of their environment. There is a transition toward more defined motor skills, improved vision, independence, and overall growth (not to mention, many begin teething!).
The real reason our babies’ sleep appears to ‘regress’  during such developmental milestones, is because like us, babies process information during their sleep. Their little brains are so busy practicing new skills, perceiving, exploring and experiencing in their waking hours, that they can have difficulty ‘switching off’ when it is time to sleep.
It is usually at times like this, many of us will experience some level of insecurity around our parenting ability, and many consider introducing formula (if exclusively breastfeeding) – assuming this fussy behaviour means our babies are not getting enough from us. In many cases this is not true, however, if you are concerned, I recommend consulting your local healthcare practitioner or lactation consultant.
Whilst it can be time consuming and frustrating, third time around, I  am a little more relaxed. knowing this stage does pass, and that it doesn’t mean; I am a bad parent, my child is ruined, my child is sick, I’ll never get sleep again, or my milk supply is compromised.

My Top Tips for dealing with this “Regression”

  1. Keep to a routine – Children thrive on knowing what to expect, and consistency makes them feel secure. Keep your sleep associations the same, and be sure attentive to your child’s sleep cues so they are not becoming overtired at these times (this will make it even more difficult for them to get to sleep and stay asleep). Remaining constant will give them the best chance at getting back on track as soon as that sun begins to shine again. An earlier bedtime (6:30-7pm) may help prevent them becoming overtired, and dream feed scheduled 3 hours after bedtime can grant you some extra mileage overnight between feeds
  2. Incorporate some wind down time before naps and bedtime to give your child the best chance of relaxing before sleep – sleep associations such as dark room, white noise, swaddle, sleep bag song/book and comforter will cue that it is time for bed
  3. Keeping your baby swaddled for bedtimes can help calm them; many babies still have an active moro (startle) reflex at this age!
  4. Introduce a safety approved comforter (breathable cotton muslin squares are ideal). If breastfeeding, it can help to express breast milk on it and/ or placing it down your top so it smells like you and can encourage the bond. In my experience, babies with comforters are happier, and more secure; which can make for a much smoother progression through milestones and other life transitions
  5. Be flexible – if it means more naps in the carrier, pram, or car than normal, then so be it. Having your child sleep by any means, is going to be better than entering a battle of wills trying to get them to only sleep in their cot! Tip: Skin on skin can do wonders for connection at these times
  6. Acknowledge your child’s feelings around sleep ” I know you are having a hard time getting to sleep. You’re feeling frustrated because you’re so tired, and you can’t get to sleep. I love you, and I am here to help you” – Be prepared to spend a little more time sitting beside your baby whilst they drift off to sleep at these times, They will need the extra security!
  7. Communicate to your baby if you are going to leave the room, put them down, change their nappy, pick them up, or leave them with someone else. Communicating your intentions in advance is not only respectful, but will encourage their cooperation – which can mean more security, and less tears!
  8. Download the Wonder Weeks app on your phone so you know when and what to expect from such developmental milestones (leaps) in the first 20 months – and how to respond to your baby’s behavioural and sleep needs during these times. Note: regression at these times can last anywhere between a few days to a few weeks
  9. Allow your baby to cry in your supportive presence; with all that is going on for them at these times, feelings of frustration, confusion, exhaustion and overwhelm is common (for us as well as them!). Not all cries are a need to be rocked, bounced, fed, or have a dummy (or breast) plugged in their mouth. If you are certain you have covered the fundamentals (e.g. nappy, hunger, temperature etc), then allowing them to express their feelings through crying can be healthy, healing and contribute to better sleep at these times
  10. Avoid sleep training whilst your baby is experiencing a milestone (especially cry it out/controlled crying).
    Be patient, kind and sensitive to your baby’s needs. Extra cuddles will make them feel loved and secure…. And know (like everything else in the world of babies) that this too shall pass!

Until next month, with love,
Sophie & Jett xoxox

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