Maternal depression and infant daytime cortisol

The effect of maternal depressive disorder on infant daytime cortisol production was studied in three groups of infants; one group with mothers with comorbid depression and anxiety (n=19), a second group with mothers with depression only (n=7), and a third group with non-depressed mothers (n=24). The infants' cortisol production pattern was measured when they were 6, 12, and 18 months old in combination with repeated measures of parenting stress and depression symptoms. Multilevel modeling analyses showed that infants of mothers with comorbid depression and anxiety had relatively higher cortisol production from morning to bedtime and higher bedtime values as compared to infants of non-depressed mothers and infants of depressed only mothers when they were 6 and 12 months old, but not when 18 months old. The results were interpreted in light of possible changes in the infants' stress regulatory capacities or changes in maternal coping strategies at infant age 18 months.