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Does sleep training harm babies or cause attachment problems?

Last updated on April 10, 2026

The evidence consistently shows that sleep training does not harm babies or damage parent-child attachment. Multiple randomized controlled trials find that sleep training improves infant sleep and reduces parental stress, with no adverse effects on child behavior, emotional development, or attachment at follow-up periods of up to 5 years.

Evidence Summary

  • Data source: Multiple RCTs including Hiscock et al. (2007), Price et al. (2012), and the Gradisar et al. (2016) trial with follow-up

  • Key finding: Hiscock et al. RCT found sleep training improved maternal depression and sleep at 4 months with no harm at 2-year follow-up

  • Key finding: Gradisar et al. (2016) found no differences in attachment, emotional, or behavioral outcomes between sleep-trained and control children at 5-year follow-up

  • Key finding: Sleep training works — most infants show improved nighttime sleep within 1–2 weeks

  • Caveat: Studies primarily cover healthy infants; children with medical issues or developmental concerns may need tailored approaches

Confidence: High confidence — multiple RCTs with long-term follow-up; one of the better-studied parenting interventions in the infant literature.

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