Infertility is a term doctors use if a man hasn't been able to get a woman pregnant after at least one year of trying. Causes of male infertility include

• Physical problems with the testicles
• Blockages in the ducts that carry sperm
• Hormone problems
• A history of high fevers or mumps
• Genetic disorders
• Lifestyle or environmental factors

About a third of the time, infertility is because of a problem with the man. One third of the time, it is a problem with the woman. Sometimes no cause can be found.

If you suspect you are infertile, see your doctor. There are tests that may tell if you have fertility problems. When it is possible to find the cause, treatments may include medicines, surgery, or assisted reproductive technologies. Happily, two-thirds of couples treated for infertility are able to have babies.

NIH: National Institute of Child Health and Human Development