Sperm Antibodies

The surfaces of all cells in our bodies are coated with special proteins called antigens. In our body, development the immune system accepts these antigens and does not make antibodies against them to destroy them. Antibodies from the immune system destroy any foreign cells or proteins, which enter our bodies.

The sperm, however, does not develop until puberty and is isolated from the immune system in the ductal systems of the testicle and epididymus and vas. Antibodies are not usually made against a person’s own sperm unless a break in the system occurs and sperm comes into contact with our blood. Then antibodies can form against the antigens on the sperm surface.

After vasectomy (but also after such occurrences as testicular trauma, infection, etc.), sperm antibodies can form. A very high percentage of post-vasectomy patients can have sperm antibodies present in the blood. It is important to understand, however, that even though antibodies are present in the blood they may not be present in the semen of a post-vasectomy patient.

The lab can check for sperm antibodies with an ejaculated semen sample using an immuno-bead binding test. Sperm, which are coated heavily with antibodies, cannot penetrate the cervical mucus and cannot reach the egg to fertilize it. Antibodies can affect other aspects of sperm function as well.

Even though sperm antibodies are detected in the semen, they might not be at a high enough level as to cause impairment of fertility, and therefore not be clinically significant.

Intrauterine insemination (IUI) can be tried. This is a cost effective measure that places a concentrated sample of sperm directly into the uterine cavity by passing the cervical mucous. This is done at the time of ovulation. If IUI fails to produce pregnancy then Invitro fertilization (IVF) can be done.