Of course you should take your questions to your child’s doctor but it helps to be informed about the test for 17-OH progesterone as well as the different ways the results can be expressed.

As Diane has pointed out, there are various units of measure used to state 17-OHP serum levels. These are: ng/ml or ng/L or nmol/L. Converting from ng/ml to ng/L is easy, just multipy the ng/ml by 1000: 1 ng/ml = 1,000 ng/L

nmol/L is more complicated. A mole is the molecular weight of a molecule in grams and a nmol (nano mole) is that same weight expressed in nanograms. I couldn’t find the molecular weight of 17-OH progesterone anywhere so having nothing better to do I calculated it to be about 298 (corrections gladly accepted). Assuming that my calculation is correct a nmol of 17-OHP is 298 ng. Therefore 1 ng/ml = 1,000 ng/L = 3.35 nmol/L (1,000/298 = 3.35)

Now that relationships between the units of measurement are perfectly clear here’s some information concerning the 17-OH progesterone test taken from: http://my.webmd.com/content/asset/adam_test_17-oh_progesterone

Normal Values for 17-OHP cover a wide range:
male: 0.3 to 3.2 ng/ml = 300 to 3,200 ng/L = 1 to 11 nmol/L
female:
   day 1 to 10 of menstrual cycle: 0.2 to 0.7 ng/ml
   day 10 to end of menstrual cycle: 0.4 to 2.2 ng/ml
   pregnancy, 12th week to term: 2.2 to 12.9 ng/ml
I was unable to find any values for prepubescent females.

The above site also states that "Levels higher than 20 ng/ml may indicate CAH"
20 ng/ml = 20,000 ng/L = 67 nmol/L.  Obviously these levels would be indicative of CAH that is completely out of control.

A couple of things I get from all of this is a sense of how widely "normal" 17 OHP levels can vary and how high levels have to be before they are considered indicative of CAH. This just serves to underscore the fact that the first line of defense against over or under suppression are your own observations and experience. Put that knowledge together with your child’s levels and over time you will get a sense of what constitutes his or her "normal" range of levels.

I hope this hasn't just muddied the waters.

Joan