Jared L Moss, Lindsey E Crosnoe and Edward D Kim
Background: The populations of symptomatic hypogonadal men and men fathering children at later ages are both increasing. Infertility is a potentially detrimental and preventable side effect of exogenous testosterone therapy. While the use of commercially available testosterone products to treat hypogonadism are increasing, very little is known about their specific effects on fertility.
Methods: A PubMed literature search for the years 1944-2013 was completed focusing on studies examining the effect of testosterone replacement therapy on male fertility. A review of U.S. Food and Drug Administration Prescribing Information was performed on commercial testosterone products in the United States. The manufacturers for the testosterone products were individually contacted for additional information regarding testosterone replacement, spermatogenesis, and male infertility. Lastly, the website www.clinicaltrials.gov was accessed for active clinical trials assessing the effect of testosterone preparations on spermatogenesis and male fertility.
Results: All commercial companies referred inquiries regarding spermatogenesis and male fertility to their Prescribers Information Warning and Precautions Sections. These sections consist of a general statement explaining that adverse effects on spermatogenesis may be seen at high doses. Most of these companies have not performed product specific studies examining the effects of their preparation on spermatogenesis. As a result, the warnings used are often extrapolated from previous studies examining different testosterone products. A few testosterone preparations have product specific data, but the data is scant and very limited. Conclusion: Currently, scant data exist that are product specific to the commercial testosterone being prescribed to the hypogonadal male seen in clinical practice. More studies are needed that examine these specific products’ effects on spermatogenesis before one can make educated recommendations regarding use. Men desiring fertility should avoid exogenous testosterone use.