Prepping for bone marker lab

karyn, the recommendation is to have the test before 8:30am. The result become less accurate for comparison because the change during the day can be 40%. The results won't be meaningful without fasting and early draw.
P1NP is less variable. I hope you are having both.

@gently Thank you! After posting the question I looked back at the test results and realized the CTx hadn't been ordered, it was an NTx urinalysis. Yes, the P1NP was done as well. But both were done late morning, non-fasting, so it's back to the lab. Not sure why NTx was done. From what I've read it seems CTx is preferred.

It is very important to have the CTX as early as possible in the morning and be consistant as poissible with that time on consequent CTX blood draws. CTX is highest in the early morning and then declines. A 6:00am draw is going to be different from a 10:00am draw. And a 10;00 draw is not giving you an accurate reading of your true CTX state. CTX is variable thoughtout the day, some docs may be hesitant to use becausue results may not be based on proper compliance of draw time or diet observance..
No collegen or bone broth is to be taken 48hours prior to the draw as this also may skewresults.
Assure your doc you will follow protcal - ask if there is anything else he/she wants you to do.
Hope this helps.... Sending healing energy.

@dmshope Thanks so much for sharing all of this info! I've also read not to take biotin prior to testing, and to fast 12 hours prior. So much to learn . . .