Pregnancy and Postpartum Maternal Hair Cortisol Are Associated With Infant Development During the COVID-19 Pandemic

The longitudinal study followed 158 mother-infant pairs during pregnancy, 6 weeks, and 6 months postpartum, measuring maternal hair cortisol concentrations (HCC) as an indicator of stress. The study found that lower maternal HCC during pregnancy was associated with lower infant development scores at 6 months, as measured by the Ages and Stages Questionnaire (ASQ). There was no main effect of HCC at 6 weeks postpartum. However, a significant interaction was found between pregnancy and postpartum HCC, with mothers who had lower HCC during pregnancy and higher HCC 6 weeks postpartum having infants with lower ASQ scores. The study concluded that a transition from blunted to elevated stress activity over the perinatal period negatively impacts infant development.