They seem to prevent sperm and eggs from meeting by either immobilizing the sperm on their way to the fallopian tubes or changing the uterine lining so the fertilized egg cannot implant in it. IUDs have one of the lowest failure rates of any contraceptive method. The IUD's image suffered when the Dalkon Shield IUD was taken off the market in 1975. This IUD was associated with a high incidence of pelvic infections and infertility, and some deaths. Today, serious complications from IUDs are rare.
Complications occur most often during and immediately after insertion.
Traditional Methods Fertility awareness. Also known as natural family planning or periodic abstinence, fertility awareness entails not having sexual intercourse or using a barrier method of birth control on the days of a woman's menstrual cycle when she is more likely to become pregnant. Because a sperm may live in the female's reproductive tract for up to seven days and the egg may remain fertile for about 24 hours, a woman could get pregnant from intercourse that occurred from seven dkays before ovulation to 24 hours or more after. Methods to approximate when a woman is fertile are usually based on the menstrual cycle, changes in cervical mucus, or changes in body temperature. In this method, also called coitus interruptus, the man withdraws his penis from the vagina before ejaculation.