Associations among prenatal stress, socioeconomic status, and infant epigenetic aging

This pre-registered study investigated the associations between prenatal stress and socioeconomic disadvantage with epigenetic aging in one-month-old infants. We hypothesized that exposure to greater maternal perceived stress, maternal physiological stress, and family socioeconomic disadvantage would be associated with accelerated epigenetic aging among infants. A socioeconomically and racially diverse sample of mothers were recruited during their last 5 weeks of pregnancy, when they completed surveys on their family income, education, and perceived stress levels, and provided a hair sample to index hair cortisol concentration. At 1-month postpartum, saliva samples were collected from their infants to assess genome-wide DNA methylation (n = 159). Epigenetic age was assessed using the Horvath, PedBE, PhenoAge, GrimAge, and DunedinPACE clocks. There was no consistent association across socioeconomic and stress factors with infant epigenetic aging. Findings are situated within effect sizes reported from previous studies, and we consider the validity of applying epigenetic clocks to infant populations. The diverging effects of family income, education, perceived stress, and physiological stress on development are considered.