The shift happening in your baby’s sleep
The way young newborns sleep is not the way older babies sleep. Somewhere around 3 months, sleep begins to take on a more grown-up structure: babies start dropping into non-REM sleep as they fall asleep, the hormone rhythms that separate day from night begin to cycle, and sleep moves in cycles of roughly 50 minutes. Each time a cycle ends, your baby rises to the edge of waking. If they fell asleep on their own, they slip back under. If they fell asleep while feeding or being rocked, they wake all the way and need that help again. This isn’t a step backward — your baby has matured, and the old route to sleep can no longer paper over it.
Solving this is precisely what Actually Sleeping does. Dr. Sam writes a plan that teaches your baby to fall asleep independently, and we coach you thoroughly before night one so you start out confident. You can hear from other parents in our 4-month regression reviews.
A passing phase, or a settled pattern?
| Signs of a phase | Signs of a pattern |
|---|---|
| Came on abruptly alongside an illness or a trip | Began around 4 months and hasn’t gotten better |
| Unpredictable: some nights go fine | Most nights bring similar wake-ups at similar times |
| Brief | Going on for weeks |
| Baby settles back down without much trouble | Baby needs the whole bedtime routine repeated every time |
Why waiting it out and quick fixes fall short
The change underneath is permanent, which means there’s no finish line to wait for. Quick fixes usually relocate the problem instead of solving it — trade feeding for rocking, and now it’s rocking your baby needs at 2 a.m. Generic plans run into a separate snag at this age: some 4-month-olds do still need night feeds, so the plan has to build independent sleep while handling feeds appropriately for that particular baby. Striking that balance hinges on your baby’s feeding, growth, temperament, naps and current way of falling asleep.
Our approach to sleep at 4 months
Dr. Sam writes a plan for your baby specifically, paced to their age and temperament. Night feeds are handled according to your baby’s age, as set out in your custom plan. You receive bootcamp-style coaching before the first night, daily 1:1 check-ins, and coaching on naps until they are solid. Because habits are still newer at this age and your baby isn’t mobile yet, it’s a good moment to begin.
Our guarantee clock begins at the 10-week birthday, which means a 4-month-old qualifies: “We guarantee that your baby will sleep 8–12 hours through the night within 14 days of consistent, correct implementation of your sleep plan.” Otherwise, you receive a full refund.
If your baby’s sleep came apart around 4 months and never recovered, book a free consultation and walk us through what your nights look like right now.
Ready for help with your own baby’s sleep?
With Actually Sleeping you get 1:1 coaching built around your child: Dr. Sam writes a sleep plan for your baby, we run bootcamp-style coaching before Night 1, and we check in every day until it is working. We have coached 700+ families, collected 129 video reviews, and put our promise in writing: 8–12 hours through the night within 14 days, or a full refund.
Book your free consultation → Hear from families we’ve coached
Questions parents ask
When does the 4 month sleep regression end?
Since the change underneath it is permanent, there is no natural point at which it stops. Sleep gets better when your baby learns to fall asleep independently. That skill is what an Actually Sleeping plan centers on, supported by daily check-ins and a written guarantee.
Is it okay to sleep train during the 4 month regression?
Yes — and it is frequently a smart moment to begin, since habits are still fairly new and your baby isn’t mobile yet. At Actually Sleeping, we pace plans at this age to fit the individual baby. Night feeds are handled according to your baby’s age, as set out in your custom plan.
Could my 4 month old be waking from hunger?
It’s possible. Night feeds are handled according to your baby’s age, as set out in your custom plan. Still, hunger isn’t behind every waking; many happen at the transition between cycles. An Actually Sleeping plan changes the way your baby falls asleep.