It is of no doubt that any programme to vaccinate pregnant women will raise concerns and controversy. New vaccines cannot be tested on pregnant women but the experience on its safety has been drawn from data from seasonal flu vaccines. The swine flu vaccine is similar to the seasonal flu vaccine in many respects. The vaccine contains the inactivated (killed) H1N1 virus which is developed from the bird flu H5N1 virus-a virus to which most people have no immunity. The inactivated virus will not cause any harm to the fetus or mother and active immunity will develop. The antibody response to vaccines in pregnant women has been shown to be as effective as those who are not pregnant.