Anti-Sperm Antibodies and Infertility by Dr. Bruce Rose of Infertility Solutions, IVF PA

Anti-Sperm Antibodies

The immune system develops during infancy. Part of that development requires that the immune system determine which proteins are part of you. If a foreign protein subsequently enters your body, some cells in the immune system recognize it as foreign, create immunoglobins to attach to this foreign protein, and finally, other cells destroy these the cells containing this foreign protein. Since sperm is not present in infancy, the proteins that make up sperm are foreign to your body. The body handles this by keeping the immune system separate from the male reproductive system.

Men develop anti-sperm antibodies or immunoglobins directed against sperm if proteins from sperm bypass the natural barriers to the immune system. This may occur because of surgery or testicular trauma. Anti-sperm antibodies can attach to any protein on sperm. Head directed antibodies are more likely to interfere with fertilization than antibodies directed against proteins located elsewhere on sperm. Immunobead testing is used to locate where on sperm the immunoglobins attach.

Generally, anti-sperm antibodies may be considered a subfertility factor. The larger the proportion of sperm involved, the more likely that anti-sperm antibodies cause subfertility. Often, the existence of anti-sperm antibodies is not recognized. We screen for anti-sperm antibodies with our "profile" semen analysis. The most common cause of anti-sperm antibodies is vasectomy.

Treatment for anti-sperm antibodies should be directed at pregnancy acceleration techniques. With a significant percentage of sperm having anti-sperm antibodies, IVF may be required in order to achieve pregnancy. In fact, if only 20% of sperm have anti-sperm antibodies, fertilization with IVF is reduced by 50% (one would expect a similar reduction with natural fertilization). When head directed antibodies are involved, then fertilization problems are more likely to be more severe. Thus when IVF is required, ICSI should be used.