Adaptive changes in infant emotion regulation persist three months following birthing parent receipt of cognitive behavioral therapy for postpartum depression

BACKGROUND: Infants exposed to postpartum depression (PPD) exhibit more emotion regulatory (ER) difficulties than infants who are not. While treatments for PPD that include cognitive behavioral therapy (CBT) may adaptively alter infant ER immediately following treatment, it is unclear if these improvements persist. METHODS: This study examined if adaptive changes in infant ER persisted three months after their birthing parent completed 9-weeks of CBT for PPD. We used data from n = 35 case infants (of birthing parents diagnosed with a postpartum major depressive disorder), and n = 33 healthy control infants (born to non-depressed birthing parents and matched to case infants on age, sex and family SES). A multimethod assessment of infant ER included resting-state frontal EEG asymmetry (FA), high-frequency heart rate variability (HF-HRV), and birthing parent- and partner-reported temperamental positive affect (PA). Infant ER was examined at three study visits (V1 occurred before CBT/at baseline for control infants, V2 took place immediately after CBT (9-weeks later), and V3 was three months after V2). RESULTS: Three months after birthing parent CBT (V3), infants continued to exhibit greater left FA relative to pre-treatment [∆mean_{V1 to V3} = 0.19, [SE = 0.082], p = 0.02]-the pre-to-post treatment shift from right to left FA remained statistically significant at V3). HF-HRV at V3 also increased relative to pre-treatment [∆m_{V1 to V3} = 0.81, [0.19], p < 0.001], as did PA reported by birthing parents [∆m_{V1 to V3} = 0.64, [0.16], p < 0.001] and their partners [∆m_{V1 to V3} = 0.54, [0.18], p = 0.004]. No ER measures differed between case and control infants at the three-month visit. CONCLUSIONS: Treating PPD may set infants on a persistent adaptive ER trajectory.