The association between prenatal maternal stress, infant brain volumes, and temperament during the COVID-19 pandemic
Abstract
Prenatal maternal stress (PNMS) is associated with altered trajectories of infant socio-emotional and brain development, including brain structures such as the amygdala and prefrontal cortex (PFC). During the COVID-19 pandemic, which was a major global stressor, PNMS was significantly elevated, yet the impact on infant neurodevelopment remains uncertain. The objective of the present study was to determine whether PNMS during the pandemic was associated with infant amygdala and PFC volumes as well as temperament. In addition, we examined whether social support and resilience during pregnancy were protective factors.
Participants were enrolled in the Canadian ‘Pregnancy during the COVID-19 Pandemic’ cohort study. Pregnant individuals had their perceived stress, pandemic-related objective hardship, mental health, social support, and resilience measured. Infant magnetic resonance imaging (MRI) scans (n =100) were conducted at 3 months of age, and parents reported on infant temperament at 6 months of age. General linear models were used to examine the associations among PNMS, brain volumes, and developmental outcomes and to assess the role of protective factors.
The results found that prenatal maternal anxiety negatively predicted 3-month left infant amygdala volumes. Smaller left amygdala volumes were also associated with greater infant 6-month negative affectivity. Maternal stress was associated with smaller infant PFC volumes, and this relationship was moderated by social support and resilience. This study provides evidence for infant brain alterations related to prenatal maternal perceived stress and anxiety, indicating that the impact of PNMS on infant development during the COVID-19 pandemic may have long-lasting implications for children’s health. Our findings suggest that social support, resilience, and mental health may be key areas for screening and intervention during pregnancy to best support healthy infant development.