Female Immunocontraceptive Vaccine - Present Status and Future Perspectives

World population is expected to rise to 9 billion in next 50 years. Between 2000 and 2030 nearly a hundred percent of the annual population growth will occur in the less developed countries of Africa, Asia, and Latin America. Apparently, there will be growing demand for suitable (discreet, simple to use, long lasting, reversible, sociologically accepted and inexpensive) methods of birth control. Immunocontraceptive vaccines seem to be a promising alternative for the population control. Studies on immunocontraceptive targets have been aimed at either gametogenic (sperm, zona pellucida) components or at sex hormones involved in the regulation of fertility. So far, the only contraceptive vaccine that has undergone the Phase II clinical trial in human model was hCG. However, there are still unknown consequences of the prolonged stimulation with this vaccine. There have been also attempts to use other reproductive hormones (GnRH, FSH) as immunocontraceptives. None of them, however, appeared to be adequate to be applied in humans due to either a lack of efficacy, costs or serious side effects. Recently, there were also published data on novel antigens of spermatogenic origin with a potential of stimulation of the production of antisperm antibodies. They provided limited contraceptive efficacy only in animal models. The article compiles the literature concerning the present status and future perspectives of immunocontraceptive strategies as well as describes different vaccine constructs under study.