The role of stress in female reproduction and pregnancy: an update.

Life exists by establishing a balanced equilibrium, called homeostasis, constantly challenged by adverse stimuli, called stressors. In response to these stimuli, a complex neurohormonal reaction exerted by the activation of the so-called stress system is initiated. The latter is activated in a coordinated fashion, leading to behavioral and peripheral changes that improve the ability of the organism to adjust homeostasis and increase its chance for survival. The stress system suppressive effects on female reproduction involve suppression of the hypothalamic-pituitary-ovarian axis at the hypothalamic, pituitary, ovarian, and uterine levels. Experimental and human data suggest that adverse prenatal stimuli, of either maternal or fetal origin, acting in the developing embryo in utero, can lead to the development of short- and long-term health disorders. These include preterm birth of the offspring, low birth weight, and the development of adult diseases ranging from the metabolic syndrome to several neurodevelopmental disorders.