Methods: This study relates to a cohort of 672 mother-baby pairs who have been followed from birth up to 6 years
of age. The sample included mothers and infants seen at all ten maternity units in a large Brazilian city. Genetic,
socioeconomic, demographic variables and postnatal characteristics were analyzed. The outcome analyzed was
overweight and/or obesity defined as a body mass index greater than or equal to +1 z-score. The sample was
stratified by breastfeeding duration, and a descriptive analysis was performed using a hierarchical logistic regression.
P-values of