Thanks Maxine,

Now that I have the correct value for ng/nmol for 17-OH progesterone here are the conversions again:

1 ng/ml = 100 ng/dl = 1,000 ng/L
and since there are 330 ng in a nmole of 17-OH progesterone,
1,000ng/L of 17-OHP is equivalent to 3.03 nmol/L (1,000/330=3.03)

The description of the 17-OHP test is at:
http://my.webmd.com/content/asset/adam_test_17-oh_progesterone