A recent study at Fort Stewart, Ga., and Hunter Army Airfield, Ga., was designed to determine whether military's women's pregnancy rates were affected by having been inoculated with an anthrax vaccine. The pregnancy rate ratio, birth odds ratio, and adverse birth outcomes ratio comparing vaccinated women with unvaccinated women were statistically insignificant. Of 4,092 women, 3,136 had received at least one dose of the anthrax vaccine, of whom 385 became pregnant. The study was not sufficiently in-depth, however, to determine conclusively whether the rate of adverse birth outcomes was higher among women who had been administered the anthrax vaccine.