If your baby has gone from “pretty ok” sleep to waking constantly, you’re not imagining it.
The phrase “4 month sleep regression” is a bit misleading because it often starts earlier than four months. A lot of families feel the shift somewhere between 3 and 6 months. And it’s usually not a true regression (your baby hasn’t gone backwards), it’s a normal maturation of sleep.
In the newborn stage, sleep is irregular but babies spend a lot of time in very different sleep patterns compared to older infants. As they mature, their sleep begins to organise into cycles that look more like adult sleep, with lighter stages and more little transitions throughout the night. That’s not a problem by itself. The hard part is that those lighter stages make wake-ups more noticeable, and some babies need a specific kind of help to move from one cycle to the next.
This is why you might suddenly see things like false starts (bedtime “works” for a short stretch, then they’re up again), naps getting shorter, or frequent night wakes that feel relentless. It can also show up as a baby who’s harder to settle, fussier in the evening, or waking early for the day. None of this means you’ve broken anything. It usually means their sleep is changing, and your current settling pattern is being tested.
One of the most frustrating parts is that many babies still wake between cycles. Adults do too. The difference is what happens next.
If your baby needs lots of support to fall asleep at bedtime (feeding to sleep, rocking to sleep, being held until fully asleep, dummy replacement) they often look for the same support when they drift into a lighter stage later on. That’s why it can start to feel like you’re doing the same thing every 45 minutes.
What actually helps tends to be a mix of protecting sleep right now (so baby isn’t spiralling into overtiredness) and gradually teaching more independent settling in a way you’re comfortable with.
During this phase, protecting day sleep matters more than parents expect. An overtired baby often has higher stress hormones in their system (cortisol and adrenaline) which can lead to more bedtime battles, more false starts, and lighter sleep overall. If naps are messy for a week or two, it can help to do whatever reliably gets them some rest (contact naps, pram naps, car naps) while you rebuild the bigger structure.
The sleep environment can matter more now too because sleep is lighter. A darker room for naps and early mornings, steady white noise if household sounds wake them, and a calm predictable bedtime routine can all reduce the number of “unnecessary” wake-ups.
Consistency is the part that most families struggle with (because you’re exhausted). If you change your approach every night, baby gets mixed signals and you don’t get enough time to see what is actually working. Consistency doesn’t have to mean leaving your baby to cry. There are responsive approaches that include reassurance and support, but they still follow a plan (and the plan stays the plan for more than one night).
Bedtime timing can also be a sneaky trigger for false starts and fragmented sleep. Too early can create repeated wake-ups because they’re simply not ready for a long stretch yet. Too late can create more cortisol and a more unsettled first half of the night. This is why a tailored plan usually looks at the whole 24 hours (wake time, nap totals, bedtime, feeds), not one isolated moment.
And yes, feeding matters. Some babies genuinely still need night feeds at this age. But when it becomes very frequent (hourly feeds), it’s often a blend of hunger, habit, and sleep association. A gentle plan can separate those needs without removing feeds your baby still needs (this is especially important for breastfed babies, reflux babies, and babies who have had slower weight gain or prematurity).
If you’re too tired to troubleshoot, here’s the quick mental check I use with parents:
1 – Is baby getting enough day sleep for their age (roughly, not perfectly)
2 – Is bedtime calm, predictable, and not rushed
3 – Is the room dark enough for early morning sleep
4 – Are you re-settling the same way each time
5 – Are you trying to change sleep without a clear step-by-step plan
If you’re reading this at 2am, and you’re on week 3+ of frequent wakes, or you feel anxious every evening because you don’t know what the night will bring, you don’t have to keep guessing.
Clear next step (and this is the one I’d actually do): book a free 15 minute discovery call so we can look at your baby’s age, feeding, naps, and what’s happening at bedtime, then tell you exactly which package fits (and whether you even need a full package).
1 – Book your free discovery call here: https://soundasleepguru.com/book-15-minute-free-discovery-phone-call/
2 – Or browse packages first (prices and what’s included): https://soundasleepguru.com/sleep-packages/
If you want, bring two things to the call (a rough nap day and last night’s wake-ups). That’s usually enough for us to spot the pattern and give you a clear way forward.