A guest post from Daisy Hall of Daisy Hall Sleep Consultancy
You finally felt like you were getting the hang of things. You survived the hazy, milk-stained blur of the fourth trimester, you worked out which cry meant wind and which meant hunger, and maybe—just maybe—your baby started giving you a glorious four or five-hour stretch of sleep at the start of the night. You breathed out. You felt human again.
And then your baby hit four months, and the wheels completely fell off.
Suddenly, you are up every forty-five minutes. Naps last the exact length of time it takes you to make a cup of tea and sit down. Putting your baby into the cot feels like trying to defuse a bomb where the slightest creak of a floorboard sets the whole thing off.
If you are in the thick of this right now, take a breath. You haven’t broken your baby, and you haven’t formed "bad habits." What you are dealing with is the notorious four-month sleep regression—and honestly, it’s often the most brutal one of the lot. Not because it’s necessarily worse than the eight-month or eighteen-month bumps, but because it blindsides you. It’s the first big hurdle right after you’ve finally found your feet.
Let’s rebrand it: It’s a progression, not a regression
The word "regression" makes it sound like your baby is going backwards. They aren’t. Biologically, their brain is doing something extraordinary, and it’s permanent.
Up until around three to four months of age, newborn sleep is fairly simple. Babies basically drift between two states: deep, quiet sleep and active, twitchy sleep. This is why you can often hoover the living room while a six-week-old snoozes in a Moses basket.
Around the four-month mark, your baby’s circadian rhythm kicks in and their sleep architecture reorganises to look much more like an adult's. Instead of two basic states, they now cycle through distinct stages of light sleep, deep sleep, and REM (dream) sleep. Every 45 to 60 minutes at night—and every 30 to 45 minutes during the day—they come up to the surface of a sleep cycle.
As adults, we do this too. We wake slightly, check the room is safe, pull the duvet up, and roll over, usually without even remembering it in the morning. Your four-month-old doesn't know how to do that yet. They surface, realise they are no longer in your warm arms or latched on, and shout for help to get back into the next cycle. Their brain has upgraded, and it’s exhausting for everyone involved.
The noise online (and why it’s okay to tune it out)
If you go searching for answers at 3 am with one eye open, you are going to get hit with some wildly polarising advice.
On one side of the internet, you’ll be told that your baby needs to "self-soothe" immediately, that feeding or rocking to sleep is a crutch you’ll regret forever, and that leaving them to cry is the only way they’ll learn. On the other side, you’ll hear that you must simply accept broken sleep for the next three years, never try to shape their sleep, and just lean into the exhaustion.
Neither of those extremes leaves much room for real life.
At Daisy Hall Sleep Consultancy, my approach is rooted in gentle, responsive, and holistic support—because every family has a completely different threshold for what works. If you are happily co-sleeping or breastsleeping (a term coined by researcher Dr James McKenna to describe the natural biological pairing of breastfeeding and bed-sharing, where mother and baby sleep close together and feed responsively with minimal waking), and everyone is getting decent rest? Brilliant. Carry on. Just make sure you are following the safer sleep guidelines from The Lullaby Trust and La Leche League GB so your sleep space is set up safely.
However, if you are touched-out, aching from lying in a rigid C-curl all night, or you desperately want your baby to do stretches in their own cot so you can actually roll onto your stomach—you don’t have to just grin and bear it. Nor do you have to resort to cry-it-out. There is a massive middle ground.
Gentle ways to help your baby link sleep cycles
You can’t stop your baby’s brain from developing, and you can’t force them to sleep. What you can do is tweak their environment, learn their optimum rhythm and gently nudge their associations so those 45-minute wake-ups become much less dramatic.
Watch the awake time, not just the clock: At four months, most babies can comfortably stay awake for around 1.5 to 2 hours between naps. If they are overtired, cortisol (the stress hormone) spikes, making it twice as hard for them to settle and stay asleep. Keep an eye out for early tired cues—red eyebrows, staring into space, or turning away from stimulation—before the full-blown grizzling starts.
Master the daytime feed: Because four-month-olds are suddenly fascinated by anything bright, the dog, and their own toes, they often get distracted during daytime feeds. They snack rather than taking a full feed, which means they wake up genuinely hungry all night to make up the calories. Try feeding in a quieter, slightly dimmer room during the day to help them focus.
Warm the cot and keep your hands on: If the transfer to the cot is waking them instantly, it’s usually the sudden drop in temperature and the feeling of falling backwards. Pop a hot water bottle in the cot for ten minutes before bedtime (always taking it out before putting baby in!) so the sheet isn't icy cold. When you lay them down, do it bottom-first, then head, and keep a firm, warm hand on their chest with a gentle shush until their breathing settles.
Pause before you pounce: This is a game-changer. Babies are noisy sleepers. They grunt, thrash their legs, and let out little cries while transitioning between sleep cycles—often while still completely asleep. If you rush in the second they make a peep, you might accidentally wake them up properly. Give it thirty seconds to see if they are actually waking or just shifting gears.
Layer your soothing: If your baby only falls asleep on the breast or being bounced on a gym ball, start introducing other ways to settle while they are already sleepy. Add a rhythmic pat on the bum, a low hum, or gentle white noise while you feed or rock. Over a couple of weeks, those secondary cues become familiar enough that you can use them to settle your baby in the cot, rather than having to pick them up every single time.
A quick word on your own sanity
This phase feels endless when you are in it, mostly because sleep deprivation messes with your sense of time. Be ruthless about lowering your standards for the next few weeks. Leave the washing in the basket, accept help if someone offers to push the pram while you shower, and remember that short naps at this age are developmentally normal—even if they are deeply inconvenient.
Your baby isn't giving you a hard time; they are having a hard time adjusting to a brand-new way of experiencing the world. Keep things simple, stay responsive, and take it one night at a time. And remember, there are always gentle ways to work towards better sleep without rigid sleep training.
Need a little more support in your corner?
If you’re feeling overwhelmed by conflicting sleep advice and want a gentle, personalised plan that fits your baby's temperament and your parenting values, I’d love to help. You can find more free resources and book a chat over at www.daisyhallsleepconsultancy.co.uk, or come and say hello on Instagram @daisyhallsleepconsultancy—my DMs are always open for tired parents.
(Heading to a LushTums postnatal class this week?) Ask about our Sleep Q and A sessions coming up!
Daisy Hall | Founder of Daisy Hall Sleep Consultancy
Daisy Hall is the founder of Daisy Hall Sleep Consultancy, supporting tired parents and caregivers with gentle, holistic, and evidence-based sleep solutions for infants and young children. Passionate about nurturing connection and respecting each child's unique developmental needs, Daisy works closely with families to improve sleep without ever using cry-it-out or controlled crying methods.
Through intimate group workshops and tailored one-to-one support, Daisy empowers parents to understand their little one's sleep biology, build calm and predictable routines, and gently resolve night wakings and nap struggles, helping the whole family get the rest they need while keeping attachment and emotional wellbeing at the heart of every step.