Diurnal cortisol variation during pregnancy in Turkish origin and non-migrant women in a German birth cohort study

Abstract

BackgroundImmigrants from Turkey experience health disadvantages relative to non-immigrant populations in Germany that are manifest from the earliest stages of the lifespan onwards and are perpetuated across generations. Chronic stress and perturbations of stress-responsive physiological systems, including the hypothalamus-pituitary-adrenal (HPA)-axis, are believed to in part mediate this relationship. Cortisol plays an important role in the association between maternal stress during pregnancy and many pregnancy-, birth- and offspring-related outcomes. We therefore examined whether maternal migrant background is associated with diurnal cortisol variation during pregnancy. Methods109 pregnant women (incl. n = 32 Turkish origin women) that participated in a multi-site prospective cohort study in Germany collected saliva samples across the day on two consecutive days around 24 and 32 weeks gestation. Hierarchical linear models were applied to quantify associations between migrant background and diurnal cortisol variation across pregnancy. ResultsWomen of Turkish origin exhibited a significantly lower cortisol awakening response (CAR) and a flatter diurnal cortisol slope (DCS) compared to non-migrant women after adjusting for household income. These relationships between migrant status and diurnal cortisol variation were mainly driven by 2nd generation migrants. DiscussionA potential HPA axis dysregulation of Turkish-origin pregnant women may contribute to the intergenerational transmission of health disadvantages in this group.