Thank you, Mary.  That is why our doctor also prefers testing urine---because it factors in levels from across the entire day. 

We also look for 17-Ketosteroids, which is the urinary metabolite of the adrenal androgens---i. e. testosterone, androstenedione, and DHEA all rolled into one number---since the excess androgens are what does the damage, and not the 17-OHP, per se.  I suppose it would be like trying to assess the severity of a car accident, by going to the scene; or trying to make a determination based on the number of cars backed up on the bridge.   Looking at the 17-KS or androgens would be like being right there.  Looking at the Pregnanetriole or 17-OHP would be like counting the number of backed-up cars.

Anyway, thanks again for posting!