There is evidence that preterm infants of migrant mothers are at a higher risk of adverse perinatal outcomes than those of native-born mothers, and that human milk feeding is beneficial to infants' neurodevelopment. Using the United Nations Human Development Index (HDI) to classify mother's country of origin, we investigated whether type of neonatal feeding (human milk vs. mixed milk vs. exclusive formula milk) affected preterm newborn neurodevelopment varying across different HDI categories (Italian native-born vs. high HDI migrant vs. low HDI migrant) up to 2 years of age. Neurodevelopment of 530 infants born in Italy at ≤32 weeks of gestational age and/or weighing <1500 g was measured at 3-, 6-, 9-, 12-, 18-, and 24-months corrected age (CA) using the revised Griffiths Mental Development Scale 0-2 years. The trajectories of the general developmental quotient and its five subscales were estimated using mixed models. At 24-months CA only preterm infants of low HDI migrant mothers and fed exclusive formula milk showed moderate neurodevelopment impairment, with lower developmental trajectories of eye-hand coordination, performance, and personal-social abilities. Migrant mothers from low HDI countries and their preterm infants should be targeted by specific programs supporting maternal environment, infant development, and human or mixed milk neonatal feeding. Future research should focus on a deeper understanding of the mechanisms through which type of feeding and mother migrant conditions interact in influencing preterm infants' neurodevelopment.
Keywords: low-birthweight; migrant mothers; neonatal feeding; neurodevelopment; preterm infants.