hi try this it should help you as a very good answer. from the moment they were introduced in the early 1960s birth control pills have been one of the most popular forms of contraception taken by millions of women in the united states and worldwide. when taken correctly birth control pills can be up to 99% effective in preventing pregnancy. however women who are taking birth control pills do on rare occasions get pregnant. when this happens it is most often because of something the women did (or more likely did not do) not because the pill itself somehow failed to work. read more: <link>#ixzz2os8fqcct you can get more info from the site so hope it helps. good luck
effectiveness of birth control. my girlfriend (18 years old) takes her pill exactly on time every single day (within 3 minutes of her 9:00pm time never any later). we have unprotected sex (we have already been tested and have no worry of stds) and i ejaculate inside of her. although she takes her pill exactly on time every single day is there a chance that she could become pregnant?