Experiences of discrimination during pregnancy predict altered neonatal hair cortisol at birth

Prenatal glucocorticoids (e.g., cortisol) are a widely proposed prenatal programming mechanism, yet few studies directly measure fetal cortisol. Neonatal hair provides a non-invasive method to assess fetal cortisol. The current studies test the association between maternal exposure to discrimination and fetal cortisol, as measured in neonatal hair, in two cohorts.

Study 1: Pregnant individuals (N = 65) and their neonates (61.8 % female) participated in study 1 between 2017 and 2021. Participants self-identified as Asian (6.2 %), Black (21.5 %), Latinx (35.4 %), Multiracial or Multiethnic (35.4 %), and Native Hawaiian or Pacific Islander (1.5 %). Experiences of discrimination were measured using the Everyday Discrimination Scale. Neonatal hair samples were collected close to birth (Median_days=1.30, IQR_days=0.96-2.03).

Study 1: Higher experiences of everyday discrimination among pregnant individuals were associated with lower hair cortisol levels in neonates (r = -.28, p = .031).

Study 2: Pregnant individuals of Mexican descent (N = 73) and their neonates (50.7 % female) participated in study 2 between 2017 and 2020. Participants reported on their exposure to experiences of discrimination using the Discrimination Stress Scale, and neonatal hair samples were collected shortly after birth (Median_days=13.0, IQR_days=11-18).

Study 2: Those who had higher discrimination stress during pregnancy had neonates with higher cortisol than those with low discrimination (F(1,70)= 3.78, p = .03), but this relation did not remain significant after controlling for gestational age.

Across two cohorts, higher experiences of discrimination were associated with alterations in neonatal hair cortisol. Both higher and lower neonatal hair cortisol are linked to poorer neonatal development, indicating that experiences of discrimination might be a potential source of health disparities in the next generation.