Association of infant child care with infant feeding practices and weight gain among US infants.

OBJECTIVE To assess whether child care arrangements influence infant feeding practices and weight gain among US infants. DESIGN Cross-sectional analysis of data collected by the US Department of Education, National Center for Education Statistics. SETTING A nationally representative sample of infants enrolled in the Early Childhood Longitudinal Study, Birth Cohort at baseline. PARTICIPANTS A total of 8150 infants aged 9 months. MAIN EXPOSURES Age (in months) at initiation and type and intensity of child care. OUTCOME MEASURES Breastfeeding initiation, early introduction of solid foods (<4 months), and weight gain (birth to 9 months). RESULTS A total of 55.3% of infants received regular, nonparental child care and half of these infants were in full-time child care. Among infants in child care, 40.3% began at younger than 3 months, 39.3% began between 3 and 5.9 months of age, and 20.7% began at 6 months or older. Infants who initiated child care at younger than 3 months were less likely to have been breastfed (odds ratio, 0.58; 95% confidence interval [CI], 0.43-0.74) and were more likely to have received early introduction of solid foods (odds ratio, 1.73; 95% CI, 1.43-2.04) than those in parental care. Infants in part-time child care gained 175 g (95% CI, 100-250 g) more weight during 9 months than those in parental care. Infants being cared for by relatives had a lower rate of breastfeeding initiation, a higher rate of early introduction of solid foods, and greater weight gain compared with infants receiving parental care. The early introduction of solid foods was a risk factor for weight gain. CONCLUSIONS Child care factors were associated with unfavorable infant feeding practices and more weight gain during the first year of life in a nationally representative cohort. The effects of early child care on breastfeeding and introduction of solid foods warrant longer follow-up to determine subsequent risk of childhood overweight.