Sleep Training and Infant Health Outcomes in the First Year
The current evidence does not demonstrate clear positive health or developmental outcomes from sleep training in the first year of life, though behavioral sleep interventions appear safe and do not cause harm. 1
Key Evidence on Developmental Outcomes
The most rigorous long-term study examining this question found no measurable benefits or harms:
A 5-year follow-up of a randomized controlled trial showed no differences in child mental health, emotional development, conduct behavior, psychosocial functioning, stress regulation, parent-child attachment, or maternal mental health between infants who received behavioral sleep training versus usual care. 1
The same study confirmed that behavioral sleep techniques have no marked long-lasting effects—either positive or negative—on child development. 1
What Sleep Training Does Accomplish
While sleep training doesn't improve developmental outcomes, it does address specific sleep-related issues:
Behavioral sleep interventions effectively reduce short- to medium-term infant sleep problems and maternal depression. 1
Parents and health professionals can confidently use these techniques to reduce the burden of infant sleep problems without concern for developmental harm. 1
The Broader Context of Infant Sleep
Current evidence does not establish a causal relationship between infant sleep patterns and cognitive, psychomotor, or temperament development. 2
Studies examining sleep during infancy and its effects on development have produced insufficient data to conclude causality. 2
The timing and subjectivity of developmental evaluations may prevent accurate assessment of any sleep-related effects. 2
Findings from one developmental period cannot be readily generalized to other developmental periods during infancy. 2
What Actually Matters for Infant Health
The American Academy of Pediatrics guidelines focus on safe sleep practices to reduce mortality risk (SIDS), not sleep training for development:
Supine (back) sleeping position for every sleep reduces SIDS risk (Level A recommendation). 3
Room-sharing (but not bed-sharing) decreases SIDS risk by up to 50%. 3
Breastfeeding is associated with reduced SIDS risk, with protective effects increasing with exclusivity. 3
Bedtime Routines vs. Sleep Training
Bedtime routines (distinct from sleep training) may provide broader developmental benefits:
A consistent bedtime routine can contribute to language development, literacy, emotional regulation, parent-child attachment, and family functioning. 4
Routine components include nutrition, hygiene, communication (reading, singing), and physical contact (cuddling, massage). 4
Supervised, awake tummy time is recommended to facilitate development (Level B recommendation), not sleep training per se. 3
Clinical Bottom Line
Sleep training techniques are safe to use when parents are struggling with infant sleep problems, but should not be promoted as having developmental benefits. 1 The focus should remain on safe sleep practices that reduce mortality risk 3 and establishing consistent bedtime routines that support broader family functioning. 4