Gradually, however, more and more couples opted for female sterilization, until these procedures outnumbered vasectomies by 2 to 1. Fears about the long-term safety of vasectomy were at least partly responsible for a decline in vasectomies, experts believe, along with easier and safer sterilization operations for women. Now, however, that trend seems to be reversing. The Antibody Question Concern over the long-term safety of vasectomy first arose many years ago when researchers discovered that many men produce antibodies to sperm following the operation. Fortunately, investigators have since found no evidence that this immune response causes health problems in men.
Antibodies are disease-fighting substances that circulate in the bloodstream.
Normally they protect the body from invaders such as viruses, bacteria, and foreign cells. In the case of many vasectomized men, however, the body's immune system mistakes sperm for foreign cells and forms antibodies against them. This happens because early in infancy, the immune system learns what is native to the body and what is foreign. Sperm cells are not produced until years later, at puberty. But at that time, they are essentially hidden from the immune system by barriers in the reproductive tract, so antibodies are not formed.