Baby Sleep Science Guide: Overcoming The Four-Month Sleep Regression

Healthy newborns follow a comfortable pattern. They're up two or three times a night for food and comfort, but you expect these nocturnal disturbances with a new baby.

But at three or four months of age, everything changes. Your baby now wakes at all hours of the night, and exhaustion and frustration become the norm.

The good news is you haven't done anything wrong. Your baby's new sleep pattern (or lack thereof) is a biological response known as the four-month regression.

Infant sleep expert...