Baby Sleep Regression

A sleep regression is a stretch when sleep that had been settling gets bumpy again. A baby who had been sleeping in longer pieces may wake more often. The sleep guide lists common windows around 4, 6, 8, 12, and 18 months.

How long it lasts

The guide treats these stretches as temporary, usually 2 to 6 weeks. Sleep cycles are reorganizing, or a new skill has the baby’s attention.

Keep the same bedtime routine through it. A new habit, such as feeding to sleep, is easy to start in a bumpy week and hard to drop later.

An overtired baby has a harder time on top of a regression. Check the wake windows by age so the awake stretch has not run long.

Common windows

4 Month Old Sleep ScheduleSleep starts consolidating into longer stretches. Many babies begin the move from 4 naps toward 3.
6 Month Old Sleep ScheduleRegular sleep cycles are in place for many babies. The move from 3 naps toward 2 is common in this stretch.
8 Month Old Sleep ScheduleThe guide lists 8 months as a common window, while many babies are still settling the move from 3 naps to 2.
12 Month Old Sleep ScheduleThe move from 2 naps to 1 is common around 12 to 15 months.
18 Month Old Sleep ScheduleSome toddlers start resisting the afternoon nap. Total sleep for this age stays about 11–14 hours.

Medical Disclaimer: This tool provides general reference information compiled from pediatric sleep guidelines (AAP, Sleep Foundation, NHS). Every baby develops differently. These are typical ranges, not prescriptive targets. Always consult your pediatrician for questions about your baby's feeding, growth, health, or sleep concerns. Follow safe sleep guidelines: place babies on their back on a firm, flat surface with no loose bedding.

Sources

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