Meta-analyses of placebo-controlled trials suggest that testosterone therapy in physiological doses is significantly associated with increased haematocrit, reduced high-density lipoprotein cholesterol and prostatic symptoms. 29 , 30 If prostate cancer has been excluded, there appears to be no increased risk of induction by testosterone therapy. There is inconsistent evidence regarding the risk of cardiovascular events. 29-31 A recent meta-analysis suggested increased cardiovascular risk and reported publication biases. 32 Long-term safety data are lacking, but recent reports more strongly suggest an increased risk of cardiovascular events in older men. 3 , 4 This has prompted the Endocrine Society to issue a warning statement. 5 The results and safety of long-term prospective controlled trials of testosterone therapy are awaited.
If a young man's low testosterone is a problem for a couple trying to get pregnant , gonadotropin injections may be an option in some cases. These are hormones that signal the body to produce more testosterone. This may increase the sperm count. Hedges also describes implantable testosterone pellets, a relatively new form of treatment in which several pellets are placed under the skin of the buttocks, where they release testosterone over the course of about three to four months. Injections and nasal gels may be other options for some men.