This paper discusses the analyses of antecedent correlates of the behavior of 60 infants as measured by the Brazelton Neonatal Assessment Scale on the third day after birth. The data include two sets of antecedent variables: maternal adaptation to pregnancy as reported in prenatal interviews and measured describing the conditions of labor and delivery (including duration, administration of analgesic and anesthetic medications, infant birth weight, and Apgar scores). The results indicate that both sets of antecedent variables show some relationships to infant behavior. The two perinatal variables which were found to correlate significantly with baby behaviors involve the analgesia and anesthesia administered during labor and delivery. Several explanations are offered for the drug effects. It was also found that the woman who reports a satisfying pregnancy, has no marked symptoms of anxiety, and is confident about mothering is more likely to have a motorically mature, attentive baby. Further analyses of the possible relationships between the two sets of antecedent variables indicate that the correlations between maternal adaptation to pregnancy and maternal medication during childbirth are not impressive. (SDH)