Infant Negativity Moderates Trajectories of Maternal Emotion Across Pregnancy and the Peripartum Period.

Background: Although the effects of maternal behavior on the development of child emotion characteristics is relatively well-established, effects of infant characteristics on maternal emotion development is less well known. This gap in knowledge persists despite repeated calls for including child-to-mother effects in studies of emotion. We tested the theory-based postulate that infant temperamental negativity moderates longitudinal trajectories of mothers' perinatal symptoms of anxiety and depression.

Method: Participants were 92 pregnant community women who enrolled in a longitudinal study of maternal mental health; symptoms of anxiety and depression were assessed during the second and third trimesters of pregnancy and again at infant age 4 months. A multimethod assessment of infants' temperament-based negative reactivity was conducted at infant age 4 months.

Results: Maternal symptoms of anxiety showed smaller postnatal declines when levels of infant negativity were high. Negative reactivity, assessed via maternal report of infant behavior, was related to smaller postnatal declines in maternal anxiety, while infant negative reactivity, at the level of neuroendocrine function, was largely unrelated to longitudinal changes in maternal anxiety symptoms. Infant negativity was related to early levels, but largely unrelated to trajectories of maternal symptoms of depression.

Limitations: Limitations of this work include a relatively small and low-risk sample size, the inability to isolate environmental effects, and a nonexperimental design that precludes causal inference.

Conclusions: Findings suggest that levels of infant negativity are associated with differences in the degree of change in maternal anxiety symptoms across the perinatal period.