Just to play devils advocate here----lets say he was taking it for infertility issues or associated with hypogonadism....
With the media the way it is now days, if you were in his shoes, would you want them finding out that you are shooting blanks or worse yet that you had low testosterone levels? I doubt it seriously if the team doctors have anything to do with fertility issues, although I still haven't read exactly what kind of doctor he went to see--a GP, a fertility specialist, a quack on 42nd and broadway.
Theres more to this than what we are being told.