Endocrine emergencies in pregnancy.

A number of endocrine conditions and emergencies have unique characteristics when present in the pregnant woman. Often the abnormal endocrine state affects both mother and fetus and the various diagnostic and therapeutic approaches have to be altered to avoid harming the fetus. Furthermore, the pregnant state itself may alter the natural course of the underlying endocrine condition. Prolactinomas may enlarge due to the hormonal milieu of pregnancy, causing mass effects and even apoplexy. Anticipation of this possibility and prompt recognition may prevent disastrous consequences. This stimulatory state may extend to the normal pituitary, resulting in Sheehan's syndrome. An acute form of Sheehan's may go unrecognized, leading to unnecessary maternal deaths. Autoimmune endocrine disorders may sometimes be exacerbated and at other times be ameliorated during pregnancy. Witness the development of lymphocytic hypophysitis during pregnancy, a condition best left alone if it can be diagnosed without surgery. Graves's disease usually improves during pregnancy but it may occasionally flare, resulting in potentially lethal thyroid storm. The various therapeutic alternatives for hyperthyroidism are very much affected by effects on the fetus. Cushing's syndrome has very bad consequences for the fetus and must be diagnosed and treated urgently, if not emergently. Phaeochromocytomas are always endocrine emergencies requiring urgent and sometimes emergent treatment. Hyperparathyroidism is usually mild, but severe hypercalcaemia can be a true endocrine emergency. Recognition of the interactions of these endocrine conditions and their specific treatments with the complicated maternal-fetal unit makes their diagnosis and treatment simultaneously both difficult and extremely rewarding.