Parental use of 'cry it out' in infants: no adverse effects on attachment and behavioural development at 18months.

Abstract

Leaving infant to cry it out has been the subject of discussion among researchers and parents. Nevertheless, there is paucity of empirical research investigating the association between leaving infant to cry it out and consequent crying duration and frequency, mother-infant attachment and behavioural development. The sample with complete longitudinal data comprised 178 infants and their caretakers. Parental use of 'leaving infant to cry out' and cry duration were assessed with maternal report at term, 3, 6 and 18months, and frequency of crying was assessed at term, 3 and 18months of age. Attachment was measured at 18months using the strange situation procedure. Behavioural development of the infant was assessed with two observational measures and a parent-report questionnaire at 18months. The use of 'leaving infant to crying' was rare at term and increased over the next 18months. 'Leaving infants to cry it out' at term was associated with a decrease in crying frequency at 3months. Furthermore, leaving infants to cry it out a few times at term and often at 3months was associated with shorter fuss/cry duration at 18months of age. No adverse impacts of leaving infants to cry it out in the first 6months on infant-mother attachment and behavioural development at 18months were found. Contemporary practice of some parents in the United Kingdom to occasionally or often 'leaving infant to cry it out' during the first 6months was not associated with adverse behavioural development and attachment at 18months. Increased use of 'leaving to cry it out' with age may indicate differential responding by parents related to infant self-regulation.