11-deoxycortisol in amniotic fluid: prenatal diagnosis of congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency.

The mean control level of 11-deoxycortisol as determined by radioimmunoassay in eighty-one human amniotic fluid samples was 1.20 +/- 0.07 ng/ml. Markedly elevated levels were found at term in amniotic fluid of two pregnancies with fetuses affected with 11 beta-hydroxylase deficiency, congenital adrenal hyperplasia (135.0 and 64.0 ng/ml respectively) as well as in the maternal serum of one of these cases (28.0 ng/ml). It is suggested that the determination of 11-deoxycortisol in amniotic fluid be a prenatal diagnostic test for 11 beta-hydroxylase deficiency congenital adrenal hyperplasia.