Abstract
About 12% of couples worldwide are infertile. Male factor infertility causes or is contributory to a couple's ability to conceive in approximately 50% of cases. Evidence has emerged that infertile men have poor overall health and increased morbidity and mortality, yet the causes for this are poorly understood. Although these men may appear healthy, research shows that they can harbor a wide variety of systemic diseases and illnesses that may share common links with the causes of their infertility. In fact, as semen parameters decline, their risks of several health conditions increase. In the early 1990s to the present, studies revealed that 1% to 6% of unselected infertile men seeking clinical evaluation have significant and (sometimes) life-threatening pathologies ranging from endocrine abnormalities to malignancies, developmental anomalies, and genetic diseases. Yet, despite this knowledge, for couples seeking treatment of their infertility, the female partner undergoes extensive clinical evaluation but the male partner frequently is only asked to provide a specimen for a routine semen analysis. This review focuses on the current understanding of the association of the genetic causes of male infertility and a multitude of diseases that affect these men's overall health and their increased risk of mortality.