Effect of maternal diet quality in early pregnancy on infant anthropometry at birth and at six months of age.

The aim was to investigate the association between maternal diet quality in early pregnancy and infant anthropometric outcomes at birth and at six months of age among Brazilian women with overweight. Secondary analysis of a randomized clinical trial included 238 pregnant women and 192 mother-infant pairs with data at birth and six months, respectively. 24-h dietary recalls were obtained between 3 and 15 gestational weeks. Diet quality was evaluated using the Diet Quality Index Adapted for Pregnant Women (IQDaG). Linear regression models adjusted for potential confounding factors, including treatment group (control/intervention) were used to investigate the associations. Higher maternal diet quality (IQDaG score) was positively associated with birth weight (β = 12.311; 95% CI: 5.163, 19.458; p = 0.001), birth weight Z-score (β = 0.024; 95% CI: 0.007, 0.041; p = 0.007), birth length (β = 0.050; 95% CI: 0.015, 0.084; p = 0.005), birth length Z-score (β = 0.030; 95% CI: 0.008, 0.052; p = 0.008), and ponderal index (β = 0.044; 95% CI: 0.010, 0.078; p = 0.011), and inversely associated with small for gestational age (β = -0.006; 95% CI: -0.009, -0.002; p = 0.002) and low birth weight (β = -0.007; 95% CI: -0.010, -0.003; p < 0.001). No significant associations were observed with others neonatal indicators. At six months of age, IQDaG score was positively associated with infant length (β = 0.061; 95% CI: 0.019, 0.103; p = 0.004) and length-for-age Z-score (β = 0.204; 95% CI: 0.007, 0.401; p = 0.006), but not with weight-related indicators. These findings suggest that better maternal diet quality in early pregnancy is associated with more favorable fetal growth and may be particularly related to linear growth during infancy.