Sub-optimal birth weight in newborns of a high socioeconomic status population

Objective: To compare sub-optimal birth weight (2,500 to 2,999 g) term newborns to appropriate for gestational age (birth weight ≥ 3,000 g) term newborns, regarding maternal data and newborn morbidity and mortality. Methods: Single term newborns, appropriate for gestational age from a high socioeconomic population (n = 1,242) with birth weight ranging from 2,500 to 2,999 g (Group I) were compared to 4,907 newborns with birth weight ≥ than 3,000 g (Group II). Maternal and newborn characteristics were compared between the groups. The Mann-Whitney test, χ2 test and multivariate analysis were used. The significance level adopted was p < 0.05. Rresults: The frequency of sub-optimal birth weight newborns in the population studied was 20.2%. There was a significant association between sub-optimal birth weight and maternal weight before pregnancy and body mass index, maternal weight gain, height, smoking habit and hypertension. Newborns’ 1-minute Apgar score, neonatal hypoglycemia, jaundice, transient tachypnea, congenital pneumonia and hospital stay were significantly different between the groups (p < 0.05). A significant relationship could not be established with the 5-minute Apgar score and pulmonary hypertension in both groups. Neonatal mortality did not differ between the groups. Cconclusions: Socioeconomic status was not a risk factor for sub-optimal birth weight in the studied population. Genetic and environmental factors were associated to sub-optimal weight and neonatal diseases. According to these data, this group of newborns should receive special attention from the health team.