Waking every hour is different from normal night waking. A newborn surfacing every two to three hours to feed is expected. Hourly waking, night after night, usually means something specific is interrupting the transition between sleep cycles.
Work through these in order.
The causes, in the order worth checking
1. Overtiredness. The most missed cause by a wide margin. A baby who has been awake too long produces more cortisol, which fragments sleep rather than deepening it. Check the wake windows: roughly 45 to 60 minutes for a newborn, 75 to 90 minutes at three months, two to three hours at six months. If daytime naps have been short, the night will be worse, not better. Counter-intuitively, the fix is often more daytime sleep and an earlier bedtime.
2. Sleep cycle length. Babies cycle roughly every 45 to 60 minutes, and surface briefly at the end of each one. If something wakes them fully at each surfacing, you get hourly waking. This is why the next three items matter so much.
3. Sound that starts and stops. A sound machine on a timer, a television that goes off, household noise that comes and goes. Each change re-alerts a baby who was about to resettle. If you use sound, keep it continuous all night at a steady level around 50 dB, well away from the cot.
4. Temperature drift. Rooms get coldest in the early hours. A baby dressed correctly at bedtime can be too cold by 3am. Check the back of the neck, not the hands or feet. Aim for roughly 16 to 20°C and dress one thin layer more than you are comfortable in, counting a sleep sack as a layer.
5. Hunger that is real. Growth spurts genuinely increase night feeds, and they pass in a few days. But if hourly waking is always resolved by a two-minute feed, the feed may be a settling habit rather than hunger.
6. Sleep associations. If your baby falls asleep being rocked, fed or held, then surfaces at the end of a cycle and finds those conditions gone, they will call for them again. This is the single most common cause of hourly waking beyond the newborn stage.
7. Developmental leaps. Rolling, crawling and pulling to stand all disrupt sleep because babies practise new skills at night. Give extensive practice time during the day.
8. Age-specific regressions. Around 4 months sleep architecture matures permanently and night waking increases; 8 to 10 months brings crawling and separation anxiety. These pass in two to six weeks.
What tends to work
Protect daytime sleep rather than restricting it. Keep sound continuous. Keep the room temperature steady. Give your baby the chance to resettle for 60 to 90 seconds before intervening — a surprising amount of hourly waking resolves itself if nobody interrupts it. And where possible, let the last part of falling asleep happen in the cot.
When to see your doctor
See your doctor if hourly waking comes with poor weight gain, feeding difficulty, snoring or laboured breathing, pauses in breathing, persistent ear-pulling with distress, fever, or if your baby seems in pain. Sleep that suddenly fragments without an obvious cause is worth a check rather than a strategy.