Accuracy of Labcorp and/or Quest labs in the United States?

I’m a 31 year old male with secondary hypogonadism. 6’2’’ 195, probably 15 percent body fat

3 years ago, I started clomid 50mg 5x a week. Eventually my testosterone got into the 800s and so the dose was reduced to 4x a week. About a year ago due to slowly increasing lab numbers, again the clomid was reduced to 50mg 3x a week.

Back in September 2019, I had some labs taken and my free testosterone was around 15 and my total was in the mid-700s.

A few weeks ago, I had some really strange labs from LabCorp, with my total testosterone, free testosterone, and hematocrit coming back the highest ever by a substantial margin:
–Hematocrit of 50 in range of 37.5 to 51 ((I donated blood a few days latter and my hematocrit also came back at 50… so this one is probably accurate imo))
–Total testosterone of 1065 ((H)) in a range of 264-916
–Free testosterone of 32.4 ((H)) in a range of 8.7-25.1
– LH/FSH/E2 were not taken at this time.

The free testosterone and the total are the highest they have ever been by a huge margin. I have never tested over 820 total test and about 20 free testosterone before.

Also, in the last two months, I have stopped taking nightly 2mg melatonin which I have taken seriously every night for over ten years and I also increased Wellbutrin from 150 to 300mg daily. I have also lost about 12 pounds of fat through tons of road biking during this time period.

Based on this scenario, is it more likely that (1) the LabCorp labs were an error or (2) they are accurate and I can probably keep dropping the clomid? If the labs are real — I wonder if even one 50mg tablet a wek could do the trick. As everyone on this board seems to know — clomid is great for energy and muscle gains, but terrible for libido and my case has been no different. I hope that on a miniscule clomid dose my libido could improve… or maybe I have a chance of dropping it.

Overall question is how often do LabCorp and/or Quest screw up? I’m not convinced my Dr will run labs again in the near future. Is there any chance that stopping ten years of nightly melatonin could of made such a huge difference? From my research, it appears that high dose melatonin suppresses LH/FSH in medical testing… however, the melatonin doses involved were orders of magnitude higher than I have ever taken.

Would appreciate any expertise.

Labcorp and Quest participate in the CDCs hormone standardization program for T with their LC/MS method. Labcorp achieved an accuracy of +/- 6% for >95% of the testsamples over the entire ref range, Quest ‚only‘ had 75% of the samples in this range.

In general variability is <10% for the LC/MS method.


Thank you! Those are some great numbers to have. Very helpful. Interested in any evidence from others, to include whether stopping melatonin after ten years of daily supplementation could lead to such a dramatic shift in hormones?