Australian doctors are conducting the first human safety tests of an experimental anti-pregnancy vaccine designed to immunize women against a hormone that is necessary to maintain pregnancy.
So far, none of the 30 women being tested (who are all sterile) has shown ill effects, according to Australian physician Warren Jones. The vaccine has successfully stopped pregnancies from advancing in baboons. Details of the research and clinical trials were outlined at a recent immunology convention in Toronto.
"We're still studying this. But the feasibility of the concept does seem to have been established," said the vaccine's developer, Dr. Vernon Stevens of Ohio State University.
The vaccine is designed to work by neutralizing a hormone, human chorionic gonadotrophin (HCG), that is produced soon after conception and is essential to maintaining pregnancy.
Stevens said the vaccine was developed by linking part of synthetic HCG with diphtheria toxoid. The chemical linking, when injected into baboons, prompted the formation of antibodies to attack HCG and halt the animal pregnancies.
He said the necessary antibodies have shown up in the Australian women tested to date.