Objective: To examine the effects of maternal depression on infant social engagement, fear regulation, and cortisol reactivity as compared with maternal anxiety disorders and controls and to assess the role of maternal sensitivity in moderating the relations between maternal depression and infant outcome.
Method: Using an extreme-case design, 971 women reported symptoms of anxiety and depression after childbirth and 215 of those at the high and low ends were reevaluated at 6 months. At 9 months, mothers diagnosed with a major depressive disorder (n = 22) and anxiety disorders (n = 19) and matched controls reporting no symptoms across the postpartum year (n = 59) were visited at home. Infant social engagement was observed during mother-infant interaction, emotion regulation was microcoded from a fear paradigm, and mother's and infant's cortisol were sampled at baseline, reactivity, and recovery.
Results: The infants of depressed mothers scored the poorest on all three outcomes at 9 months-lowest social engagement, less mature regulatory behaviors and more negative emotionality, and highest cortisol reactivity-with anxious dyads scoring less optimally than the controls on maternal sensitivity and infant social engagement. Fear regulation among the children of anxious mothers was similar to that of the controls and their stress reactivity to infants of depressed mothers. Effect of major depressive disorder on social engagement was moderated by maternal sensitivity, whereas two separate effects of maternal disorder and mother sensitivity emerged for stress reactivity.
Conclusions: Pathways leading from maternal depression to infant outcome are specific to developmental achievement. Better understanding of such task-specific mechanisms may help devise more specifically targeted interventions.