Test Overview

A semen analysis measures the amount of semen a man produces and determines the number and quality of sperm in the semen sample.

A semen analysis is usually one of the first tests done to help determine whether a man has a problem fathering a child (infertility). A problem with the semen or sperm affects more than one-third of the couples who are unable to have children (infertile).

Tests that may be done during a semen analysis include:

• Volume. This is a measure of how much semen is present in one ejaculation.
• Liquefaction time. Semen is a thick gel at the time of ejaculation and normally becomes liquid within 20 minutes after ejaculation. Liquefaction time is a measure of the time it takes for the semen to liquefy.
• Sperm count. This is a count of the number of sperm present per milliliter (mL) of semen in one ejaculation.
• Sperm morphology. This is a measure of the percentage of sperm that have a normal shape.
• Sperm motility. This is a measure of the percentage of sperm that can move forward normally. The number of sperm that show normal forward movement in a certain amount of semen can also be measured (motile density).
• pH. This is a measure of the acidity (low pH) or alkalinity (high pH) of the semen.
• White blood cell count. White blood cells are not normally present in semen.
• Fructose level. This is a measure of the amount of a sugar called fructose in the semen. The fructose provides energy for the sperm.