My 4-month-old baby keeps waking up at night, is it sleep regression?

4-Month Sleep Regression — You're Not Doing Anything Wrong 💙

In short: Yes, this looks like a classic 4-month sleep regression. It typically lasts 2-6 weeks and is a sign of your baby's brain development.

Why does it happen?

At 4 months, your baby's sleep cycles go through a major change:

• Sleep cycles transform into adult-like patterns — cycling between light and deep sleep
• Between cycles (every 45-90 minutes) there are brief awakenings
• Your baby doesn't yet know how to fall asleep on their own — they need your help
• This is a healthy developmental milestone, not a problem

What helps?

• White noise — acts as a bridge between sleep cycles
• Dark room — use blackout curtains
• Consistent bedtime routine — bath, feeding, lullaby, same order every night
• Earlier bedtime — overtired babies sleep worse
• Patience — this phase is temporary, it will pass

What other moms are saying?

"It lasted 3 weeks for us. The hardest part was everyone telling me to 'just let them cry.' I didn't, and it sorted itself out. Patience really is key."

"My mother-in-law said 'they're hungry, give formula' but my doctor said breast milk only until 6 months. I trusted my doctor, and I did the right thing."

When should you see a doctor?

• Your baby looks sick, not just fussy (fever, vomiting)
• They're refusing daytime feeds
• It's lasting longer than 8 weeks

This information is not a substitute for medical advice.