Pregnancy as an intergenerational conduit of adversity: how nutritional and psychosocial stressors reflect different historical timescales of maternal experience

Macronutrients consumed by the pregnant mother enter her homeostatically regulated metabolism, which buffers the fetus against short-term increases or deficits in intake. In contrast, hormones that coordinate this homeostasis, including cortisol, respond acutely to stressors. Because maternal cortisol crosses the placenta to influence fetal tissues, transient stress activation during pregnancy can durably change offspring development. These principles lead to the expectation that adversity during pregnancy will primarily impact offspring via acutely-responsive systems like stress physiology, while intergenerational effects of the mother's protein–energy nutrition will reflect her chronic nutritional experiences across pre-pregnant life. Thus, although developing fetal systems are sensitive to maternal psychosocial and nutritional adversity in utero, the intergenerational impacts of these systems reflect distinct timescales of maternal experience.