Baby Sleep Regression Calculator

❓ What is a Sleep Regression?

A sleep regression is when your baby or toddler who has been sleeping well suddenly starts waking frequently at night, fighting naps, or having difficulty falling asleep. These are normal, temporary phases that happen at predictable ages as your child goes through major developmental leaps.

The most challenging is typically the 4-month regression, which represents a permanent change in sleep architecture. Others are usually shorter-lived but can be equally exhausting for parents. Understanding when to expect them helps you prepare mentally and practically for these difficult periods.