Antisperm antibody: a monkey wrench in conception/magic bullet of contraception?

Antisperm antibodies can cause infertility by interacting with spermatozoa through immunoglobulin binding protein thereby blocking their penetrance of cervical mucus and/or by interfering with sperm-egg interaction. However, these antibodies appear not to be cytotoxic to embryos since a high implantation rate and consequently high pregnancy rate were achieved by IVF-ET treatment of women with antisperm antibodies. Also the finding that these antibodies do not appear to cause any deleterious clinical symptoms and have yet be associated with infertility suggested that sperm antigens are promising candidates in the development of immunocontraceptives. Some synthetic peptides corresponding to segments of human sperm antigens have effectively induced infertility in female rats when administered as an immunogen. Different peptides, adjuvants and routes of administration should be studied to determine the optimum conditions for inducing high antisperm antibody titers in the host. Moreover, identification of various steps and factors that are involved in regulating the production of antisperm antibodies such as immunoglobulin binding factor may open new paths in the treatment of immunological infertility and at the same time lead to a more effective immunocontraceptive.