Male athletic activities and their effects on semen and hormonal parameters

Infertility is generally defined as the inability to conceive a pregnancy or the failure to do so within a reasonable period (typically 12 months). Approximately 85% of couples conceive a first pregnancy within 12 months. The prevalence of infertility has increased over the past 10 years, with approximately 10 million affected couples in the United States. Roughly 40% to 50% of infertility is either due to, or is contributed by, a male factor. Given how common the condition is, men and their partners are understandably concerned and interested in identifying and eliminating risk factors for male infertility. This article reviews the available literature on various aspects of male infertility related to athletic pursuits. These include the effects of exercise on semen parameters, hormonal axes, and testicular health. Due to the prevalence and particular relevance of anabolic steroid use by athletes and the impact of steroid use on fertility, this topic is also reviewed.