Efficacy of Contraception Methods

Contraception is the use of a method, device or medication that helps prevent pregnancy. Some methods of contraception also protect a person from acquiring sexually transmitted infections. The efficacy of contraception methods is measured according to the percentage of women who experience unintended pregnancy in a year while using a particular contraception method, according to the University of California Davis.

Classifications

• Classifications of contraception include natural methods, barrier methods, surgical methods and oral/hormonal methods. Examples of the natural method are abstinence, withdrawal and rhythm (based on counting days/calendar tracking). Barrier methods include condoms, spermicides, intrauterine devices and diaphragms. Hormonal methods include birth control pills, Depo-Provera and birth control patches. Surgical methods include vasectomy and tubal ligation/sterilization.

Functions

• Barrier methods stop the sperm from contact with the eggs. These methods also help prevent sexually transmitted infections, but they can be fiddly to use and may interrupt sex at times.

  Hormonal methods work to suppress ovulation by thickening the cervical mucous with the help of two artificial hormones: estrogen and progestin. As a result, fertilization becomes difficult to achieve. Pills, a hormonal method of contraception, are taken orally by women every day. It does not interfere with sex and lowers the risk of womb and ovarian cancer. Depo-Provera is a hormonal injection given every three months to women who think they may forget taking a daily pill.

  Natural withdrawal method or coitus interruptus is a male-control method of contraception used to avoid the contact between sperm and egg in the vagina. Abstinence is refraining from having sex, which offers 100 percent protection from pregnancy as well as transmission of sexually transmitted infections.

  Other natural methods of contraception are based on the signs that the female body gives off, such as mucous changes and basal body temperature.

Efficacy

• The two rating systems that measure the efficacy of birth control methods are the "perfect rate" and the "typical rate." Perfect rate estimates how well a birth control method performs when used as prescribed. Typical rate, on the other hand, shows how the method performs when all the errors and problems that people usually encounter are considered.

  The male condom showed a failure rate of 15 percent with typical use and 2 percent with perfect use; spermicides show 29 percent and 18 percent, respectively; diaphragm shows 16 percent and 6 percent; Depo-Provera, 3 percent and 0.3 percent; intrauterine device (ParaGard), 0.8 and 0.6 percent; withdrawal shows 27 percent and 4 percent; birth control patch, 8 percent and 3 percent; vasectomy, 0.15 percent and 0.10 percent; and ligation/sterilization shows 0.5 percent and 0.5 percent.

Considerations

• The efficacy of a contraceptive method largely depends on the user and how he or she uses it. When choosing a contraceptive method, it is important to consider factors such as efficacy, reversibility, privacy, cost, side effects and cultural preferences.

Statistics

• The Guttmacher Institute reveals that the oral birth control pill is the most widely used method of contraception in the U.S. with 30.6 percent, followed by tubal ligation at 27 percent and the male condom at 18 percent. Most women ages 30 and under use the pill while those who are ages 35 and above rely on sterilization. Condoms are used mostly by the teen population.