What Are Antisperm Antibodies?
Antibodies are proteins produced by the immune system that fight against infection and protect you from becoming ill in the future. Antisperm antibodies are formed when the immune system mistakenly sees the sperm in a man’s semen as an invader.
These antibodies then attack the sperm cells, damaging or killing them.
When a large number of antisperm antibodies come into contact with sperm, the potential for the sperm to fertilize an egg becomes greatly reduced. As a result, a couple may have a difficult time getting pregnant. This is a condition known as immunologic infertility.
The presence of antisperm antibodies is fairly uncommon, and can be made by both men and women. However, it is rare for infertility to occur solely because of sperm antibodies.
What Causes Antisperm Antibodies?
Normally, the testicles prevent the sperm from coming into contact with other areas of the body. However, sperm antibodies can develop when sperm comes into contact with the immune system.
Antisperm antibodies can be produced by a woman’s body if she is allergic to semen. The sperm is killed by antibodies in the woman’s vagina.
This cause of infertility is considered rare, and is not fully understood by doctors.
If you are a couple that is having difficulty getting pregnant your doctor might suggest fertility testing. This includes checking for antisperm antibodies.
Antisperm antibody tests look for antibody proteins that are known to be harmful to sperm, whether in the semen, blood or vaginal fluids. The test is performed by using a sample of sperm, and a substance is added that only binds to affected sperm.
Experts differ on the need for the test as the results may not affect the treatment. However, an antisperm antibody test might be performed if one the following conditions are met:
- Determining the cause of infertility is not possible.
- Unclear results from a different fertility test.
For men, an immunobead binding test can be performed on the sperm after providing a semen sample. Antiglobulin reaction testing may also be performed on the blood.
With women, sperm immobilization testing can be performed with a sample of blood. In some situations, your doctor might check your cervical mucus in order to detect the presence of any antisperm antibodies.
Experts disagree on whether it is necessary to test for antisperm antibodies. Some argue that we don’t have sufficient evidence to determine the best options for people with antibodies who want to have children.
If you’re a man, your doctor might prescribe medication to decrease your body’s immune response. This could reduce the number of antibodies that you have and increase your chances of pregnancy in a female partner.
For women, intrauterine insemination (IUI) is a treatment that has been shown to increase the odds of becoming pregnant. This procedure involves a doctor injecting the sperm directly into the uterus, which prevents the sperm from coming in contact with any antisperm antibodies in the vagina.