congenital adrenal hyperplasia (CAH) is an autosomal recessive disease caused by the deficiency of enzymes required in the synthesis of adrenocortical hormones[1]。 According to the type of enzyme deficiency, it can be divided into 21-hydroxylase deficiency (21-OHD), 11 beta hydroxylase deficiency (11 beta-OHD), 3 beta hydroxysteroid dehydrogenase deficiency (3 beta-HSD), 17 α-hydroxylase deficiency (17 α-OHD), 20,22-carbon chain enzyme deficiency, steroid hormone acute regulatory protein (StAR) deficiency and 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) deficiency, etc. Among them, 21-OHD is the most common, accounting for about 90% to 95% of CAH; 11 β-OHD is the second, accounting for 5% ~8%; 3 β-HSD, accounting for approx.<1%; Other types Rare[2,3]。