Modern misconceptions and urban legends have given rise to a great deal of false claims:

• The suggestion that douching with any substance immediately following intercourse works as a contraceptive is untrue. While it may seem like a sensible idea to try to wash the ejaculate out of the vagina, it is not likely to be effective. Due to the nature of the fluids and the structure of the female reproductive tract – if anything, douching spreads semen further towards the uterus. Some slight spermicidal effect may occur if the douche solution is particularly acidic, but overall it is not scientifically observed to be a reliably effective method.
• It is a myth that a female cannot become pregnant as a result of the first time she engages in sexual intercourse.
• While women are usually less fertile for the first few days of menstruation,[25] it is a myth that a woman absolutely cannot get pregnant if she has sex during her period.
• Having sex in a hot tub does not prevent pregnancy, but may contribute to vaginal infections.
• Although some sex positions may encourage pregnancy, no sexual positions prevent pregnancy. Having sex while standing up or with a woman on top will not keep the sperm from entering the uterus. The force of ejaculation, the contractions of the uterus caused by prostaglandins[citation needed] in the semen, as well as ability of sperm to swim overrides gravity.
• Urinating after sex does not prevent pregnancy and is not a form of birth control, although it is often advised anyway to help prevent urinary tract infections.[26]
• Toothpaste cannot be used as an effective contraceptive[27]