The earliest recommended age for formal sleep training is 16 weeks adjusted age. This means that for babies born at full term (37+ weeks gestation), sleep training can begin at 16 weeks old. If your baby was born before 37 weeks, you’ll need to add the number of weeks they were born early to the 16-week guideline.
Example: A baby born at 35 weeks would wait until they are 18 weeks old before beginning sleep training.
Newborns do not yet have a fully developed circadian rhythm, which means their sleep patterns can be unpredictable. Their bodies need time and exposure to natural light to gradually establish a biological sleep-wake cycle. Until around 16 weeks, it’s completely normal for babies to have inconsistent sleep schedules, and they need gentle, responsive care as they adjust to life outside the womb.