ABSTRACT
Objective@#To explore the association between exclusive breastfeeding and sleep onset delay among school aged children, and to provide a reference for promoting childhood sleep health.@*Methods@#A total of 10 686 children aged 7-12 years old were recruited from 17 primary schools in Shanghai using the multi stage sampling method from April to June 2019. The duration of sleep onset delay and exclusive breastfeeding were identified using the Children s Sleep Habits Questionnaire and a self designed questionnaire, respectively. The association between the duration of exclusive breastfeeding and the score and the risk of sleep onset delay were estimated using linear regression and a Logistic regression model, respectively.@*Results@#After adjusting for confounding factors, compared with never exclusive breastfeeding, the score of sleep onset delay decreased by 0.07, 0.08 and 0.05 in cases that involved exclusive breastfeeding for less than 3 months, 3-6 months and more than 6 months, respectively; and the odds of sleep onset delay decreased by 39.0%(OR=0.61, 95%CI=0.47-0.79), 41.1%(OR=0.59, 95%CI=0.47-0.75) and 21.1%(OR=0.79, 95%CI=0.65-0.96), respectively. Similar findings were observed in analyses stratified by gender, although the association was stronger among boys. Moreover, administration of probiotics or yogurt only improved sleep onset delay in those who were exclusively breastfed for no more than 6 months.@*Conclusion@#Longer durations of exclusive breastfeeding were associated with a lower risk of sleep onset delay among school aged children. However, exclusive breastfeeding for over 6 months diminished the protective effect that was otherwise observed on sleep onset delay.