Coca-cola was used as an after-sex Spermicide in America until the 1960s.  Many women in third world countries still use it as an after-sex douche, hoping to kill sperm. Recent research proved that the soda’s acidity does not kill sperm.

Research team led by Deborah Anderson, a professor in obstetrics and gynecology at Harvard Medical School conducted a placebo controlled clinical trial to test the potential of coca-cola as a contraceptive.

The study showed that coca-cola was able to immobilize only 30 percent of the sperms within an hour. Research team found that coca-cola douches increased the forward velocity of healthy sperms by almost 18 cm/hour, making the well placed healthy sperms to reach the cervix within seconds.

Anderson said that the soft drink also damages the top layer of cells within the vagina, removes healthy bacteria and makes a woman more prone to sexually transmitted disease.

She added, "There is the simple fact that there are much more effective and easy-to-use methods of contraception widely available."