Other significant adverse effects of testosterone supplementation include acceleration of pre-existing prostate cancer growth in individuals who have undergone androgen deprivation; increased hematocrit , which can require venipuncture in order to treat; and, exacerbation of sleep apnea .  Adverse effects may also include minor side-effects such as acne and oily skin, as well as, significant hair loss and/or thinning of the hair, which may be prevented with 5-alpha reductase inhibitors ordinarily used for the treatment of benign prostatic hyperplasia , such as finasteride .  Exogenous testosterone may also cause suppression of spermatogenesis , leading to, in some cases, infertility.  It is recommended that physicians screen for prostate cancer with a digital rectal exam and prostate-specific antigen (PSA) level before starting therapy, and monitor PSA and hematocrit levels closely during therapy. 
Great article, well written and god conclusions of collected data.
How ever I am still curious if creating a “shortage” of sperm and decrease of testosterone by cycles of repeated ejaculations during a short period of time, maybe during the course of hours followed by “rest-days” if that over time would provoke the body to produce more Testosterone and sperm in a response to “progressive overload”.
Since this is the way the body handles a lot other things that challenges it´s system with everything from resistance-training, “repeated skin-abrasion”, bacteria and even some toxins.
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