One of the most prominent among these stories involves carbonated drinks. Usually, the stories list things like Coca-Cola or Sprite, though most any carbonated soda drink will do. As a pseudo-testament to the prevailing popularity of this story, it was referenced in the Anne Rice erotic novel “Belinda” and actually put through a scientific test on the Discovery Channel show “Mythbusters.” The stories generally say that the use of these drinks as a contraceptive involves shaking the cans and spraying it into the vaginal cavity, where the acidic content will theoretically kill sperm cells. Sadly, as scientific testing has proved, this method doesn't exactly work.
In a similar vein to the above, another idea that people have had over the years is that rinsing out the sperm can work. This is a fairly flexible myth, taking on a variety of forms in different areas. In some cases, there are as many ways to rinse out the sperm as there are people telling the story. These include taking a shower or bath immediately after, using a liquid to rinse out the sperm from the vagina (some variations of the carbonated drink myth involve this), and having the woman urinate. While some experts say that showering or bathing after sex could have a psychological effect, preventing conception using this tactic is nothing more than a myth.
Other people believe that it is impossible for a woman to get pregnant if she does not experience orgasm. If the media is to be believed, that would mean that most women in the US can never get pregnant. The fact is, experiencing an orgasm – or any sexual stimulation at all, really – is compeltely and utterly unnecessary to achieve pregnancy. This myth is often connected to the one that states that certain positions during sex prevent pregnancy. Both are ridiculous when it comes down to it, though the latter has some more outrageous claims. A particularly outrageous one claims that having intercourse standing up, in a closet, during a full moon is the best possible birth control. Sadly, according to statistics, there are some people out there that believe this.
The “withdrawal” method, which involves having the man “pull out” before achieving orgasm, can also be categorized as a myth. The release of sperm does not always accompany the male orgasm, with some men being able to release semen into the woman repeatedly without achieving orgasm. Even if the male orgasm is accompanied by the release of sperm, there are other factors that make this tactic highly dubious in the best of circumstances. For one thing, most males release a small amount of fluid prior to orgasm that contains some sperm. Also, even if the fluid is released outside the body, if the sperm manage to make it into the vagina, then there is still a chance of pregnancy. Consider that these cells are very microscopic and the fluid may be difficult to differentiate from vaginal secretions during sex. Make a microscopic mistake --- and you've got yourself a situation.