Hi Curious,
As Kat has said levels usually go up after the ACTH stimulation test.
I have pasted a link below regarding 3Beta CAH diagnosis in adults (hope you can get it as it looks like it has pasted haywire off the page). It says, that to the writer's knowledge that "no adult woman, with normal genitalia, has been diagnosed with 3 Beta CAH".
I've been looking into this on behalf of a friend and it's been quite a saga tracking down all the ends - especially for the more rare forms of CAH. This woman's doctor has ordered everything that I have suggested and now her baseline 17-hydroxypregnenolone has come back elevated (2,720 ng/dL) along with some elevated androgen levels. Now we are just hoping that they did a post ACTH level on her 17-ohpreg when they did her ACTH stimulation test.
(PS). I will check this link after I have posted and if it is not able to be retrieved I will repost it!
http://books.google.com.au/books?id=4bwGinwF82YC&pg=PA187&lpg=PA187&dq=17-hydroxypregnenolone+levels&source=web&ots=K170xyN4Ln&sig=Bk11Ek8AZMXNNcvUEiF7iSlPfJc&hl=en&sa=X&oi=book_result&resnum=3&ct=result
