A multi-systems approach to understanding the effects of antenatal distress: biological underpinnings of perinatal depressive symptoms and biobehavioural outcomes in the child

Evidence linking maternal antenatal depression with an increased risk of altered biological and behavioral outcomes in offspring is substantial. However, knowledge concerning the underlying mechanisms is strikingly less advanced. The current dissertation addresses this gap by adopting a multi-systems approach and prospectively investigating three main biological pathways, involving stress and inflammation, possibly underlying the effects of maternal antenatal depression on infants’ early development, taking into account the potential buffering role of postnatal maternal care. One-hundred-ten healthy pregnant women, together with their offspring, were studied from late pregnancy to three months after delivery as part of the Effects of Depression on Infants (EDI) Study. In Chapter 3, cross-sectional associations between maternal depressive symptoms and stress-related biology in late pregnancy and soon after delivery were examined. Chapters 4 and 5 investigated the prospective associations between antenatal variations in maternal depressive symptoms, stress and inflammation and infant behavioral and biological outcomes at birth (Chapter 4) and 3 months after delivery (Chapter 5). Lastly, Chapter 6 explored the moderating role of maternal caregiving in the association between prenatal maternal influences and 3- month-olds’ bio-behavioral outcomes. Current findings indicate that antenatal depressive symptoms are associated with an altered diurnal cortisol pattern and heightened inflammation in late pregnancy and independently predict 3-month-olds’ negative affectivity. Additionally, this thesis provides evidence that variations in maternal stress-related biology during pregnancy are associated with offspring physiological and behavioural outcomes and that the impact of antenatal maternal cortisol on infant cortisol stress reactivity may be moderated by maternal sensitive caregiving. Despite the fact that replication of these findings in larger and different samples is needed, our results are in keeping with the hypothesis that maternal antenatal stress exerts a programming effect on offspring bio-behavioral development and that the impact partially depends on the quality of the early rearing environment