The P300 and late positive potential in pregnancy prospectively predict increases in depressive and anxious symptoms in the early postpartum period.

Postnatal depression and anxiety disorders pose a major burden on maternal mental health. While psychosocial risk factors for perinatal depression and anxiety are well-researched, there is a dearth of research examining neural biomarkers of risk for postnatal increases in depression and anxiety. Previous studies suggest two different event-related potentials, the P300 and the late positive potential (LPP), may predict the course of depressive and anxious symptoms in non-perinatal populations. In a sample of 221 perinatal women, the present study utilized an emotional interrupt task administered in pregnancy to examine whether antenatal P300 and LPP amplitudes may predict change in depressive and anxious symptoms from pregnancy to the early postpartum period. Zero-order correlations and linear regressions revealed that a reduced antenatal P300 to target stimuli and an enhanced LPP to positive infant images were uniquely associated with postnatal depressive and anxiety symptoms, respectively, and that these ERPs were independent predictors beyond antenatal self-report measures of psychological symptoms. Furthermore, individuals with increased depressive symptoms in pregnancy exhibited a stronger negative association between antenatal P300 amplitude and postnatal depressive symptoms. The present findings underscore the possibility that the measurement of ERPs during pregnancy could serve as a screening tool for risk for perinatal depression and anxiety, and thereby assist with identifying at-risk individuals who might benefit from prevention efforts.