You will need to produce a semen sample. A semen sample is often collected by masturbation. You can do this in a private room or in a bathroom at your doctor's office or clinic. If you live close to your doctor's office or clinic, you may be able to collect the semen sample at home.

• Collect the semen sample into the container your doctor gives you.
  • Wash and dry your hands and penis.
  • Ejaculate into the container. Do not use any lubricant or saliva. Do not use a regular condom to collect the semen. The powder in a condom can kill sperm. Collect the entire amount of semen you produce.
  • Keep the semen close to body temperature. A good way to do this is by keeping the semen container in an inside pocket. Avoid getting the semen hot or cold.
  • If you'd prefer to collect the sample without masturbating, your doctor may give you a special condom to wear during sex to collect the semen.
• If you collected the sample at home, take it to the lab or clinic within 1 hour after you collect it.

Since semen samples may vary from day to day, two or three different samples may be checked within a 3-month period. This helps to get accurate testing.

A semen analysis to test how well a vasectomy has worked is usually done 12 weeks after the vasectomy.

Getting a semen sample does not cause any discomfort.

There are no known risks from having this test.

Results of a semen analysis are often ready within a day.

• Volume. A high or low semen volume may cause fertility problems.
• Liquefaction time. If semen takes longer than usual to liquefy, this may be a sign of an infection.
• Sperm count. A low or absent sperm count can cause fertility problems and may be linked to certain conditions. These may include orchitis, Opens dialog, varicocele, Opens dialog, Klinefelter syndrome, Opens dialog, radiation treatment to the testicles, Opens dialog, and diseases that can cause shrinking of the testicles.
• Sperm morphology. The shape of sperm can affect how well they move and penetrate an egg. Sperm that have two heads or two tails, a short tail, a tiny head (pinhead), or a round (rather than oval) head may not function as well. Some of these sperm are usually found in a semen sample. But having a lot of these sperm may make it harder to fertilize an egg.
• Sperm motility. Sperm must be able to move forward (or "swim") through cervical mucus to reach an egg. A high percentage of sperm that can't swim well may make it harder to fertilize an egg.
• pH. A high or low semen pH can kill sperm or affect how well they can move or can penetrate an egg.
• White blood cell count. A high number of white blood cells and bacteria in the semen may be a sign of infection.

If problems are found, more testing may be done. Other tests may include measuring hormones, such as testosterone, Opens dialog, luteinizing hormone (LH), Opens dialog, follicle-stimulating hormone (FSH), Opens dialog, or prolactin, Opens dialog. A small sample (biopsy, Opens dialog) of the testicles may need to be checked if the sperm count or motility is extremely low.