Birth-Related Stressors, Social Reward Responsiveness, and Postpartum Depressive and Anxiety

Abstract

Birth-related stressors are associated with increased risk for postpartum depression and anxiety. Yet, many women endorsing these experiences do not develop postpartum symptoms, raising questions about vulnerability factors. There is a need to identify factors contributing to the likelihood of experiencing birth-related stressors as well as underlying processes that shape mental health outcomes in the context of birth-related stressors. Research has shown a prospective association between reduced neural reward responsiveness and depression. Findings with anxiety symptoms are less consistent. Further, stressful life events moderate the effects of reward processing on subsequent depression symptoms. Reward processing may be one factor influencing the relationship between birth-related stressors and postpartum depression and anxiety. For this study, women (n=120) completed self-report measures to assess depressive, anxiety, and traumatic intrusions symptoms across the peripartum period (i.e., 2nd trimester, 3rd trimester, 8-weeks postpartum). At 8-weeks postpartum, participants completed the Birth Experience Interview to capture dimensions of birth-related stressors (i.e., overall severity, violations of expectations, loss of control). Further, during electroencephalogram data collection, participants completed a Social Incentive Delay task to measure responses to positive feedback for a personally-salient social reward (i.e., cute photo of their own infant) vs. negative feedback (i.e., boring image). Participants also completed a monetary incentive delay to measure neural response to monetary reward for comparison. Analyses focused on the reward positivity to positive feedback, adjusting for negative feedback (RewP residual), an index of reward processing (Cz, 250-350 ms). Results indicated more self-reported life stress events were associated with more loss of control and violations of expectations. Social RewP was associated with greater PPD symptoms but did not remain significant when covarying for antepartum symptoms. Social RewP was associated with greater postpartum anxiety even when accounting for antepartum symptoms. Social and monetary RewP moderated associations between violation of expectations and postpartum traumatic intrusions. Violation of expectations was associated with greater traumatic intrusions only for those with relatively enhanced RewP. Results support the importance of considering dimensions of birth-related stressors and the utility of ERPs in measuring individual differences in reward processing. Specifically, ERPs can be used to better understand processing underlying postpartum psychopathology.