With a total testosterone in the normal range, you do not have primary gonadal failure.
On some labs, however, low end would be 300 ng/ml. I don't see your lab reference range.
Even if the total is low, it is a spot test and not conclusive of anything. You need to see free and bioavailable testosterone along with sex hormone binding globulin.
You might have hypothyrodism: Just as an example'. This can throw off a total testosterone measurement. So can any illness that is chronic, or adrenal dysfunction.
To get a good hormonal picture:
testosterone, free testosterone, TSH, T4, sHBG, and an andrenal panel
As well as exam with all routine labs.
See an endocrinologist. There is no way in clinical medicine that we would conclude you need to go on permanent testosterone replacement at this point, or even any replacement, not necessarily.
This is not testosterone at this point without further testing.
I am a double board certified US doctor and I was ranked at the 100th percentile in endocrinology on the American Medical Boards. If you would like to go into a comprehensive approach beyond this question, find me, Dr. Thomas, in medical by request.
OK, so that is an initial answer….
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