Causes of Infertility in Men

Infertility in men is often caused by problems with making sperm or getting the sperm to reach the egg. Problems with sperm may exist from birth or develop later in life due to illness or injury. Some men produce no sperm, or produce too few sperm. Lifestyle can influence the number and quality of a man's sperm. Alcohol and drugs can temporarily reduce sperm quality. Environmental toxins, including pesticides and lead, may cause some cases of infertility in men.