Maternal adversities during pregnancy and cord blood oxytocin receptor (OXTR) DNA methylation.

The aimof this study was to investigate whether maternal adversities and cortisol levels during pregnancy predict cord blood DNAmethylation of the oxytocin receptor (OXTR). We collected cord blood of 39 babies born to mothers participating in a cross-sectional study (N=100) conducted in Basel, Switzerland (2007-10). Mothers completed the Inventory of Life Events (second trimester: T2), the Edinburgh Postnatal Depression Scale (EPDS, third trimester: T3), the Trier Inventory of Chronic Stress (TICS-K, 1-3 weeks postpartum) and provided saliva samples (T2, T3) formaternal cortisol profiles, as computed by the area under the curve with respect to ground (AUCg) or increase (AUCi) for the cortisol awakening response (CAR) and for diurnal cortisol profiles (DAY). OXTR DNAmethylation was quantified using Sequenom EpiTYPER. The number of stressful life events (P=0.032), EPDS score (P=0.007) and cortisol AUCgs at T2 (CAR: P=0.020; DAY: P=0.024) were negatively associated with OXTR DNAmethylation. Our findings suggest that distinct prenatal adversities predict decreased DNAmethylation in a gene that is relevant for childbirth, maternal behavior and wellbeing of mother and offspring. If a reduced OXTRmethylation increases OXTR expression, our findings could suggest an epigenetic adaptation to an adverse early environment. [ABSTRACT FROM AUTHOR]