Background: Growth velocity in the first months of postnatal life has been associated with later overweight and obesity.
Objective: We analyzed prenatal and postnatal factors in association with weight, length, and growth velocities in the first 3 mo of life.
Design: We estimated weight, length, and instantaneous weight- and length-growth velocities (in g/d and mm/d) in 1418 term infants at 1 and 3 mo of age and evaluated the following potential determinants: maternal prepregnancy body mass index (BMI), 1-h plasma glucose concentrations during pregnancy, smoking, socioeconomic status, parity, paternal BMI, parental heights, and infant feeding, gestational age, and sex.
Results: Maternal obesity and plasma glucose concentrations were associated with the weights and lengths of offspring at birth but not at 1 and 3 mo after birth. In contrast, there was no association between paternal BMI and anthropometric measures of offspring at birth, but by 3 mo of age infants of obese fathers had significantly higher weights and weight-growth velocities than did infants of fathers with a normal BMI. Maternal weight gain was a significant predictor of weight at birth and 3 mo of age. Exclusively breastfed infants had a slower weight-growth velocity as early as 1 mo of age compared with exclusively formula-fed infants.
Conclusions: In the first 3 mo of life, the positive associations between maternal obesity, plasma glucose concentrations, and infant anthropometric measures at birth seem to progressively fade away, whereas the emerging association with paternal BMI may indicate an early postnatal influence of paternal genetics. Among the determinants we evaluated, some are potentially modifiable, such as maternal gestational weight gain and infant feeding. The identification of optimal patterns of growth remains crucial before providing any clinical recommendations.