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What is Which drugs are used for prenatal therapy of congenital adrenal hyperplasia? and explain in detail?
High risk pregnancies should be staed of Dexamathasone, that readily crosses placenta, in an amount of 20 mu/kg in 2-3 divided doses. This surpasses secretion of steroids by fetal adrenals, including secretion of fetal adrenal androgens. If staed 6 weeks of gestation, it ameliorates virilization of external genitals in affected female fetus. Ref: Kligman, Behrman, Jenson, Stanton (2008), Chapter 577, "Congenital Adrenal Hyperplasia", In the book, "Nelson's Textbook of Pediatrics", Volume 2, 18th Edition, New Delhi, Page 2364