Stress During Pregnancy

Abstract

High levels of stress during pregnancy are associated with a number of adverse psychological and physiological outcomes for mother and child. These effects seem to be transmitted in part by one of the major stress-responsive systems, namely the hypothalamic-pituitary-adrenal (HPA) axis, which includes the hormone cortisol. However, as inconsistent study results indicate, methodology poses a substantial challenge to the investigation of stress during pregnancy. For example, although measures of maternal psychological stress and stress hormones are independently related to adverse pregnancy outcome, they seldom have been found to correlate with one another directly. Repeated measurement of psychological and biological responses to acute standardized stress challenges appears to reveal stronger associations. This article reviews the literature on experienced stress and stress hormones in pregnant women and presents studies that used standardized stress challenges (e.g., the Trier Social Stress Test, the cortisol response to morning awakening) to examine maternal stress reactivity more systematically. This review also takes a look at the few studies that examined the protective effects of psychological and psychosocial resources or stress interventions on experienced stress and stress hormones in pregnant women. Overall, results indicate that baseline stress hormone levels advance incrementally during gestation, presumably to prepare mother and fetus for delivery, while responses to acute stress appear to be increasingly attenuated. Moreover, the acute maternal stress response seems to be predictive of neonatal birth outcome and maternal well-being postpartum. Preliminary findings also suggest that much can be done toward coping with stress during pregnancy. Further research and a closer collaboration between science and clinical practice are required.