Breastfeeding, Mother-Child Dyads of Interaction, and Neurodevelopment of Preterm Children: A Longitudinal Study of Feeding Methods During the First Two Years.

OBJECTIVE: Our objectives were as follows: (1) to compare cognitive, motor, language, and social performance, parenting skills, and mother-child interactions among preterm children exposed to different feeding practices (exclusive breastfeeding, mixed feeding, and formula feeding) during the first two years of life; and (2) to examine the associations between the feeding type, risks and protective factors, and neurodevelopmental outcomes (cognitive, motor, language, and social domains) in these population in the first two years of life. METHOD: A total of 116 preterm children (<32 weeks gestational age-GA) and their mothers were recruited from a public hospital in southern Brazil and followed at a neonatal clinic. Children were organized into three groups based on feeding at NICU discharge (exclusive breastfeeding, formula, or mixed feeding). Assessments were conducted at 4, 8, 12, 18, and 24 months of corrected age using the BSITD-III and additional validated instruments measuring environment stimulation, daily activities, maternal knowledge, breastfeeding experience, and mother-child interactions. RESULTS: Clinical and sociodemographic factors were similar across feeding groups. Group comparisons showed that exclusive breastfeeding was associated with higher motor scores at 12 (p = 0.015) and 24 (p = 0.026) months, higher cognitive scores at 12 (p = 0.049) and 18 (p = 0.013) months, and higher language scores at 12 (p < 0.001) and 18 (p = 0.014) months compared to formula feeding. In the social domain, the exclusive breastfeeding group consistently outperformed the formula group across most time points, although a temporary dip was observed at 18 months. Mixed feeding showed intermediate patterns. Children in the exclusive breastfeeding group also demonstrated higher maternal parenting skills and stronger mother-child interactions across time. Longitudinal analyses revealed that the quality of mother-child interactions predicted better motor, cognitive, language, and social outcomes, while clinical vulnerabilities (e.g., prolonged NICU stay, BPD, leukomalacia) negatively influenced trajectories. CONCLUSIONS: Exclusive breastfeeding and responsive mother-child interactions emerged as consistent protective factors across developmental domains, buffering the adverse effects of clinical risks. Breastfeeding not only enhances maternal engagement but also contributes to more favorable motor, cognitive, language, and social outcomes in preterm children. Supporting breastfeeding and promoting sensitive caregiving practices are essential strategies for optimizing developmental trajectories and improving the quality of life in this vulnerable population.