Infertility is not being able to conceive after a year of regular, unprotected sex. About one-third of infertility is caused by male factors and one-third are caused by female factors. In the remaining cases, the cause is unknown or is due to problems with both partners.

Men are considered infertile if they:

  • Produce too few sperm cells
  • Produce sperm cells of poor quality
  • Have chronic problems with ejaculation

The Male Reproductive System
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Portions of the brain called the pituitary gland and hypothalamus, as well as male reproductive organs such as the testes affect fertility in men. Problems in any of these areas may decrease fertility.

In about half of the cases, a cause cannot be found. Some factors that can contribute to infertility include:

  • Genetics diseases, such as Klinefelter syndrome and Sertoli-Leydig cell syndrome
  • Exposure to workplace chemicals or heavy metals, such as primarily lead and cadmium
  • Tobacco use and marijuana use
  • Varicocele —enlarged veins within the scrotum
  • Abnormal hormone levels
  • Infections
  • Physical abnormalities
  • Cancer
  • Medications
  • Obesity
  • Chronic diseases, such assickle cell anemia
  • Excessive physical activity
  • Anti-sperm antibodies