Association of age of initiation and type of complementary foods with body mass index and weight-for-length at 12 months of age in preterm infants

To assess whether in very preterm infants (1) body mass index (BMI) Z-score and weight-for-length (WtFL) Z-score at 1 year of age and (2) head growth from discharge to 1 year are associated with breastfeeding at discharge and the age of onset and type of complementary foods. Observational cohort study. Infants started on only ready-made complementary (RMC) feedings at ≤26 weeks adjusted age had the highest adjusted BMI Z-score and WtFL Z-score at 1 year of age. Adjusted change in fronto-occipital circumference was highest in infants either discharged on breastmilk or receiving home-made complementary food with/without RMC (HMM) at ≤26 weeks adjusted age. Infants started on RMC ≤26 weeks adjusted age had the highest BMI Z-score and WtFL Z-score at 1 year. Head growth from discharge to 1 year was highest in infants either discharged on breastmilk or receiving HMM at ≤26 weeks adjusted age.