Ancillary test for congenital adrenal hyperplasia (CAH), particularly in situations in which a diagnosis of 21-hydroxylase and 11-hydroxylase deficiency have been ruled out; for confirming a diagnosis of 3-b-hydroxydehydrogenase (3-b-HSD) deficiency and 17-alphahydroxylase deficiency; and as part of a battery of tests to evaluate females with hirsutism or infertility, both of which can result from adult-onset CAH.