Effects of Intrauterine Growth and Gestational Age upon Infants' Early Psychomotor Development in Brazil

: In a sample of 245 Brazilian infants, the effects of intrauterine growth and gestational age upon psychomotor development were studied through ages 4 to 18 mo. Gestational age was more important than intrauterine growth in determining psychomotor development in the first 18 mo. of life. Intrauterine growth had a significant but smaller and more stable effect than gestational age upon psychomotor development at all ages. Maternal parity, interval between the birth of the child studied and the next oldest sibling, 5-min. Apgar score, and socioeconomic status were also relevant to psychomotor development at these early ages.