Coca-Cola douches were a part of folklore about birth control during the 1950s and 1960s, before effective contraceptive methods were readily available. It was rumored that the acidity of Coca-Cola killed sperm, and the classic coke bottle provided a convenient "shake and shoot" applicator. Recently, an old study from our group confirming the spermicidal effects of various Coca-Cola formulations was awarded the 2008 IgNobel prize in chemistry. The press releases surrounding our IgNobel award might have repopularized this method, and soft drink douches are apparently still used to prevent pregnancy in resource-poor settings. There are, however, many reasons why women should not rely on this method.
