Birth Control Effectiveness
A woman's choice of a birth control method is a significant decision concerning her body and her life. In the attempt to find reliable information, women encounter contradictions and confusing data -- theories presented as fact, distorted statistics, and suppression of information about harmful effects. There can be a drastic difference between what the medical professionals say and what women experience.
Effectiveness of Birth Control
Self Help research has found that effectiveness statistics are misleading. Proponents of the Pill and IUD deceive the consumer because they compare theoretical effectiveness of the Pill and IUD with use-effectiveness of local or natural methods, making the Pill and IUD appear more effective than they actually are.
The effectiveness of a particular method of birth control is estimated in two ways: its use-effectiveness and its theoretical effectiveness. The use-effectiveness is the way the method works in actual practice, measured by finding out how many women get pregnant while using a particular method of birth control for a specified period of time. If 100 women use a method for one year and three of them get pregnant, the method would be described as 97% effective in 100 "women-years" of use, or as having a failure rate of 3%. Researchers presume that married women have coitus three times weekly and their statistics assume a "married model." Women who have coitus more or less frequently would not be able to apply these probabilities to themselves; they can only use them to compare methods.
Estimates of theoretical effectiveness are arrived at through mathematical formulas. The assumption is that the method works in an ideal way and that it is being used perfectly. This estimate serves little purpose except to measure the gap between the way a method should work and the way it actually does work.
When we compare birth control methods, using the same yardstick, pills and IUD's have the same effectiveness as foam plus condoms and diaphragms. The theoretical effectiveness of the Pill is virtually 100%, but the use-effectiveness, is estimated to be between 90% and 96%. The theoretical effectiveness of foam plus condoms is virtually 100%, and the use-effectiveness is estimated to be 95%.
When considering the safety of a method, many women want to know if it will keep them "safe" from getting pregnant, but what they are actually talking about is the effectiveness of a method, not the hazards of using it. Women who are concerned about the safety of various methods want to know how the method will affect their health. For instance, natural and local methods are "safe" because they have no harmful effects on a woman's body and no woman has ever died from using these methods. On the other hand, drugs such as the Pill reach every cell in the body and can have harmful effects on organs and body metabolism. Devices, such as the IUD, are known to risk damaging the reproductive organs as well as increase the risk of pelvic infection (PID).
Material is adapted from the unpublished manuscript written by the Federation of Feminist Women's Health Centers, Women's Health In Women's Hands, 1978, Los Angeles, CA.
