Additive effects of maternal depressive symptoms during pregnancy and three years after childbirth on offspring psychiatric symptoms in early childhood

Introduction: Themechanisms underlying the effects ofmaternal prenatal stress on foetal development remain elusive. One hypothesis is that maternal stress leads to increased cortisol blood concentrations, which in turn may overstimulate the secretion of placental corticotropin releasing hormone (CRH) into the foetal circulation. However, whether acute stress-induced rises in maternal cortisol affect foeto-placental CRH levels is unknown. We therefore aimed at exploring the association between the acutematernal psychobiological stress response as well as chronic maternal stress perception and foeto-placental CRH levels. Methods: We examined thirty-four healthy pregnant women (37.4±4.0 years) undergoing second-trimester amniocentesis. The amniocentesis served as a naturalistic stress situationduringwhich we repeatedly obtained questionnaires on maternal acute stress perception and saliva samples for cortisol analysis. We furthermore monitored maternal cardiac activity continuously (i.e., heart rate, heart rate variability). Thewomen also responded to the social overload scale of the Trier Inventory of Chronic Stress (Schultz and Schlotz, 1999). CRH levels were analysed from an amniotic fluid aliquot. Results: The amniocentesis induced significant changes in maternal stress perception, salivary cortisol, and cardiac activity. No significant association between the acute psychobiological stress response and amniotic CRH was apparent (all p> .10). However, maternal chronic social overload was positively correlated with CRH levels (Kendall’s tau= .34, p= .02). Conclusions: The current findings provide evidence thatmaternal chronic stress affects placental CRH secretion. However, we cannot exclude that a different or longer timeframe might be required to detect an association between acute maternal stress and foeto-placental CRH. Further studies are called for.