Prenatal Stress and Socioeconomic Status as Predictors of Placental Methylation in Pregnant People.

Abstract

Despite growing interest in placental epigenetics, the combined impact of prenatal stress and socioeconomic status (SES) on placental methylation is still largely understudied. We conducted a study to examine the associations of prenatal stress and socioeconomic factors (household income, Hollingshead socioeconomic index) with placental methylation. Pregnant people (n = 143; M _age = 25.66) in their second or third trimester (M _{gestational age} = 23.11 weeks) completed self-report questionnaires including demographic and socioeconomic information and ratings of perceived stress in the past month. Placenta tissue samples were collected after birth, from which placental genomic DNA was extracted to assess methylation levels at the NR3C1 promoter region. Multiple regression analyses were conducted with prenatal stress, household income, and Hollingshead index predicting methylation at the different CpG glucocorticoid receptor sites, controlling for maternal age, smoking status, gestational age at delivery, and infant sex. Prenatal stress predicted NR3C1 methylation at the CpG8 and CpG9 glucocorticoid receptor sites. Household income was a significant predictor of methylation at the CpG9 site. Hollingshead index was not associated with methylation at any site. The independent effects of prenatal stress and SES demonstrate the need for healthcare providers to recognize the psychological and socioeconomic influences on maternal-fetal health.