ABSTRACT
The major role of glucocorticoids in the foetus is to prepare it for transition from an intrauterine to an independent existence. At physiological doses, glucocorticoids are responsible for maturation of the foetal lung, thyroid, gastrointestinal tract, adrenal medulla and numerous other tissues. They are responsible for the induction of various enzyme systems that are necessary after birth but which have little or no function prenatally, and they also stimulate the deposition of glycogen in the foetal liver. In some species these functions are closely linked to the mechanisms involving parturition. At pharmacological doses and beyond, however, glucocorticoids (both natural and synthetic) are potentially harmful to the developing embryo/foetus and a review of such consequences is the primary aim of this chapter. Since corticosteroids play an essential and intrinsic role in the stress response in mammalian species, the effects of stress on in utero development are also reviewed.
