Antisperm Antibody Test
An antisperm antibody test looks for special proteins (antibodies) that fight against a man's sperm in blood, vaginal fluids, or semen. The test uses a sample of sperm and adds a substance that binds only to affected sperm.
Semen can cause an immune system response in either the man's or woman's body. The antibodies can damage or kill sperm. If a high number of sperm antibodies come into contact with a man's sperm, it may be hard for the sperm to fertilize an egg. The couple has a hard time becoming pregnant. This is called immunologic infertility.
A man can make sperm antibodies when his sperm come into contact with his immune system. This can happen when the testicles are injured or after surgeries (such as a biopsy or vasectomy) or after a prostate gland infection. The testicles normally keep the sperm away from the rest of the body and the immune system.
A woman can have an allergic reaction to her partner's semen and make sperm antibodies. This kind of immune response is not fully understood but may affect fertility. This is a rare cause of infertility.
Why It Is Done
The antisperm antibody test may be done if:
- A cause for infertility cannot be found. Experts disagree about the usefulness of the test because the result may not change the treatment.
- The results from another fertility test are not clear.
How To Prepare
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).
For women, a blood sample is taken from a vein in the arm.
For men, a semen sample is collected after the blood and vaginal fluid samples are taken. You should not release your sperm (ejaculate) for 2 days before the test. It is important to not go longer than 5 days before the test without ejaculating.