The study was based on the assumption that stressors in the lives of pregnant and parenting
women are processes that affect prenatal, postpartum, and concurrent maternal hormones and
emotions and that these processes affect child temperament. The hypotheses were tested in a
group of 67 young mothers and their 3-year-old children. Mothers were clustered into groups
based on longitudinal patterns of hormones and emotions at prenatal, postpartum, and 3-year
follow-up assessments. The analyses focused on relating maternal patterns of hormones and
emotions to the child's temperament at age 3 years. Temperament was assessed by
questionnaire and observation of behavior during a challenging situation. Illustrative findings
included the following. Verbal aggression and nonverbal aggression were significantly higher in
children of mothers in the low prenatal hormone cluster than children of mothers in the
high prenatal hormone cluster. Children of mothers in the postpartum low testosterone
(T), estradiol (E2), and androstenedione (Δ4-A) and medium cortisol (Cort) cluster (mainly low hormone cluster) exhibited significantly more physical aggression than children of mothers in the medium T and Δ4-A, high E2 and low Cort cluster. Maternal patterns of hormones, emotions, and parenting attitudes and practices were related to multiple aspects of temperament when the children were age 3 years. The findings support the important role of maternal biological and psychological processes in the development of child temperament.