Responsible and informed choices for contraception begin with understanding the chances of getting pregnant using condoms, birth control pills and other contraceptives - in other words, the rate at which these various birth control techniques tend to fail. As calculated by medical scientists, the chances of getting pregnant using condoms, birth control pills and other contraceptives assume that you are using them correctly. No contraceptive will be adequately effective if it is not used appropriately.
On average, after one year, 85% of couples who are sexually active but do not use contraception will become pregnant. Those practicing only withdrawal techniques ; other so-called natural family planning techniques have a 2-9% failure rate over one year, although in practice as much as one-quarter of women will become pregnant because of errors in planning.
The two most common contraceptive methods of choice are condoms and birth control pills. Male condoms, the traditional kind, have a failure rate of 3%, although in practice the failure rate is several times this much (about 10%) because men often apply them incorrectly. Female condoms, which exist but are much less frequently used, have a failure rate of 5% when used properly - again, the effective failure rate is more than twice this because of incorrect use. Contraceptive pills come in a variety of formulations and different brand names, but overall have a failure rate of about 1-3% when taken daily, as prescribed. Hormone patches, implants, and injections are more than 99% effective.
Other, less frequently used contraceptive techniques do exist. Barrier devices inserted into the uterus (IUDs) have a 1-3% failure rate. Spermicides, which are medical substances used to kill sperm after it enters the female reproductive system, is less effective, having a failure rate of 15-20%.
The safest, but also the most permanent, contraceptive techniques are surgical: male or female sterilization. (Male vasectomies are simpler and less risky procedures, so barring other medical complications, married couples should probably consider this approach first.) In a very small percentage of such cases (much less than 1%), body tissues regenerate and again make pregnancy possible. However, in general these approaches are the most effective ways of preventing pregnancy, but are also irreversible.
It should be noted that, in every case and without exception, the rates of effectiveness rely upon you and your sexual partner always taking care to use contraceptives correctly: for example, taking the birth control pill daily, and applying condoms correctly. Improperly used contraceptives will fail more often; indeed, in some circumstances, they may offer very little real protection at all.
For this reason it is always important to understand how contraceptives work as well as the chances of getting pregnant using condoms, birth control pills and other contraceptives. Roughly half of unplanned pregnancies are experienced by women who were using contraceptives - which in many cases were used incorrectly. Using multiple contraceptive techniques can dramatically reduce the risk of pregnancy. However, the only truly safe and risk-free sexual practice is not to have sex at all.
- Sources and Further Reading -
American Pregnancy Association. "Male Condom."
Center for Young Women's Health. "Success & Failure Rates of Contraceptives."
FamilyDoctor.org. "Birth Control Options."