Developmental origins of infant stress reactivity profiles: A multi-system approach

Background: This study tested the hypothesis that maternal physiological and psychological variables during pregnancy discriminate between theoretically informed infant stress reactivity profiles. Methods: The sample comprised 254 women and their infants. Maternal mood, salivary cortisol, respiratory sinus arrhythmia (RSA), and salivary α-amylase (sAA) were assessed at 15 and 32 weeks gestational age. Infant salivary cortisol, RSA, and sAA reactivity were assessed in response to a structured laboratory frustration task at 6 months of age. Infant responses were used to classify them into stress reactivity profiles using three different classification schemes: hypothalamic-pituitary-adrenal (HPA)-axis, autonomic, and multi-system. Discriminant function analyses evaluated the prenatal variables that best discriminated infant reactivity profiles within each classification scheme. Results: Maternal stress biomarkers, along with self-reported psychological distress during pregnancy, discriminated between infant stress reactivity profiles. Conclusions: These results suggest that maternal psychological and physiological states during pregnancy have broad effects on the development of the infant stress response systems.