Surviving the 4-Month Sleep Regression
My baby hit 4 months last week… and just like that, the decent stretches of sleep we had finally started to enjoy disappeared overnight.
Suddenly she’s waking every 45–90 minutes, fighting naps like it’s her full-time job, and treating bedtime like a personal insult.
If this sounds familiar, welcome to the (very real) 4-month sleep regression. I've been googling and it really is a common feature.
What’s actually going on?
Around this age, babies’ sleep cycles mature and start looking more like adult ones. They move through lighter sleep stages more often and often can’t connect those cycles on their own yet. On top of that, they’re suddenly more aware of the world, practicing new skills (rolling, grasping, babbling), and sometimes dealing with growth spurts or teething. Result: more night wakings and shorter naps.
It’s temporary (usually 2–6 weeks), but it can feel endless when you’re living it.
What has helped us (and a lot of other moms I’ve talked to):
• Stick to a simple, consistent bedtime routine — even when it feels pointless. Bath → lotion → feed → book → lights out. Same order every night. It becomes a powerful cue.
• Watch wake windows carefully. At this age they’re usually around 1.5–2.5 hours. An overtired baby is way harder to settle.
• Put her down drowsy but awake as often as you can. This is the big one for teaching self-soothing later. Some nights it works, some nights it doesn’t — that’s okay.
• Dark room + white noise. Game-changers for us.
• During night wakings, keep lights dim, voices quiet, and interactions boring. Feed if she’s truly hungry, then straight back down.
• Lower your expectations for a bit. This phase is survival mode. Tag-team with your partner if you can, or just accept that some nights you’ll be co-sleeping on the floor next to the crib (no judgment).
A few gentle reminders:
• You’re not failing if you rock, nurse, or hold her to sleep right now. Connection comes first.
• Safe sleep still matters: back to sleep, firm flat surface, no loose blankets or toys.
• This will pass. Most babies come out the other side sleeping better once they figure out the new cycles.
Anyone else currently in the trenches with a 4-month-old (or any regression age)? Drop your tips, survival strategies, or just a “me too” below.