This is a less commonly used test used to identify problems with sperm or with cervical mucus, which is supposed to enhance sperm survival. Abnormal test results will include overly thick mucus, no sperm, or sperm clumping together, but won't always indicate a problem with the mucus. The test could determine that sperm may be absent because they were not deposited into the vagina during intercourse.

This test is used less frequently, since more effective management technologies have evolved, particularly intrauterine insemination (IUI), where sperm are placed directly in the uterus and therefore completely bypass hostile mucus, or IVF where eggs are fertilized by sperm, in a laboratory dish.