This therapy is started in the first trimester when fetal adrenal production of androgens begins but before prenatal diagnosis is done that would provide definitive information about the sex of the fetus and its disease status.
In its most severe form, called salt-wasting (or salt-losing) CAH, where there is a total or near total deficiency of the 21-hydroxylase enzyme, a life-threatening adrenal crisis can occur if the disorder is untreated.
Adrenocorticotropic hormone (ACTH)-Also called adrenocorticotropin or corticotropin, this hormone is produced by the pituitary gland to stimulate the adrenal cortex to release various corticosteroid hormones.
These include various types of malignant brain tumors, as well as leukemia and cancerous tumors of certain muscles (rhabdomyosarcoma), the adrenal glands (pheochromocytoma), or the kidneys (Wilms' tumor).
Prenatal therapy, in which a pregnant woman at risk for a second CAH child is given dexamethasone to decrease secretion of androgens by the adrenal glands of the female fetus, has been in use since 1994.