Associations of early life risk factors with infant sleep duration.

Objective: Insufficient sleep in children is associated with adverse health effects. We examined the associations of early life risk factors with infant sleep duration.

Methods: We studied 1676 mother-infant pairs in a prebirth cohort study. Main outcomes were mothers' report of their infants' average 24-hour sleep duration at ages 6 months, 1 year, and 2 years.

Results: Infants slept mean standard deviation [SD] durations of 12.2 (2.0) hours/day at age 6 months, 12.8 (1.6) hours/day at age 1 year, and 11.9 (1.3) hours/day at age 2 years. In multivariable regression models, maternal antenatal depression, introduction of solids at age <4 months, and infant TV/video viewing were associated with shorter sleep durations at both 1 and 2 years of age. Estimates were 0.36 fewer hours/day of sleep for maternal antenatal depression, 0.39 fewer hours/day of sleep if infant was introduced to solids at age <4 months, and 0.11 fewer hours/day of sleep for each 1 hour of TV viewed per week. Attendance at child care outside the home was associated with 0.18 fewer hours/day of sleep at age 2 years. At age 2 years, black, Hispanic, and Asian infants slept 0.40, 0.82, and 0.95, respectively, fewer hours per day than white infants.

Conclusions: Maternal depression during pregnancy, early introduction of solid foods, infant TV viewing, and attendance of child care were associated with shorter infant sleep duration. Racial/ethnic minority children slept fewer hours in the first 2 years of life than white children. Our results suggest that various risk factors, some potentially modifiable, are worthy of clinical consideration when addressing infant sleep duration.