Infertile couples may have more than one cause for infertility. It might take a number of tests to determine the cause of infertility. In some cases, a cause is never identified. Diagnosing male infertility problems usually involves: 

General  physical examination and medical history. This includes examining your  genitals and asking questions about any inherited conditions, chronic  health problems, illnesses, injuries or surgeries that could affect fertility. Your doctor might also ask about your sexual habits and about your sexual development during puberty. 

Semen  analysis. You  can provide a semen sample ejaculating into a special container at the semen collection room or by using a special condom to collect semen during intercourse. Semen is then sent to a laboratory to measure the number of sperm present and look for any abnormalities in the shape (morphology) and movement (motility) of the sperm. The lab will also check your semen for signs of problems such as infections.

Often sperm counts fluctuate significantly from one specimen to the next. In most cases, several semen analysis tests are done over a period of time to ensure accurate results. If the sperm analysis is normal, the doctor will likely recommend thorough testing of your female partner before conducting any more male infertility tests.

Additional tests shall be recommended which helps to identify the cause of infertility.