Expert: Sam Beckett - 8/30/2006

Question
I am confused by two writers' claims regarding optimal blood levels of testosterone in normal twenty-five year old women. One writer said that a good range for women is 50-60 ng/dL, while another writer said that it is 10-50 ng/mL. Did the second writer mean 10-50 ng/dL? If not, what would 10-50 ng/mL be in ng/dL?

Answer
Hi Anne,
It is possible that there has been some error here - the units of ml and dl are very different. One dl is 100 ml, and such disparity does not allow like for like comparison.  To bring ng/ml to ng/dl requires multiplying the ng/ml by 100. As you can see, this would create huge inconsistencies in the levels.
The testosterone levels in a woman vary depending on when during the menstrual phase the reading is taken, so this can allow for some variation in the levels. It might be an idea to contact a medical laboratory to ask for their reference ranges.
If you have further questions, please don't hesitate to contact me again.
Best wishes,
Sam