Infertility refers to a condition where there is no pregnancy, even after one year of regular sexual intercourse. It covers a broad spectrum of conditions which can be minor or serious. Infertility related to men is initially investigated usually with a physical examination along with a discussion about past and present medical history. A physical exam determines the general health of both partners. The doctor will pay special attention to the outer sex organs as well as characteristics such as breast development and body hair in both partners to check for structural abnormalities or signs of possible hormone problems. The medical history gathers information that may suggest causes for infertility in each of the partners. Issues that will be discussed during the medical history apply to both the man and the woman.

The most common cause of male infertility is low sperm count or absence of sperm in the semen.