Birth control, also known as contraception and fertility control, is a method or device used to prevent pregnancy.[1] Birth control has been used since ancient times, but effective and safe methods of birth control only became available in the 20th century.[2] Planning, making available, and using birth control is called family planning.[3][4] Some cultures limit or discourage access to birth control because they consider it to be morally, religiously, or politically undesirable.[2]