Level of education, household income, and other social factors can strongly predict effective pill use in one country but not in another (33, 94, 123, 139). In Egypt, for example, a study observed that inability to read was a good predictor of improper pill use. In Botswana and Zimbabwe, however, the same study could not identify any set of indicators that consistently identified women who use the pill incorrectly (94).

Some studies have found that younger women—adolescents, in particular—are less likely than older users to take the pill correctly (89, 94, 163). Other studies, however, have found no consistent association between age and proper OC use. Age often acts as a surrogate for other factors that influence pill use, such as education, motivation, side effects, and the client's perception of the quality of the provider-client interaction (178, 182).

Motivation to avoid pregnancy is important to effective pill use. Women who are sure that they do not want any more children typically are more effective pill users than women who do not currently desire pregnancy but who want more children in the future. In the Philippines, for example, older women, women with many children, and women using contraception to limit rather than space births had the lowest rates of pregnancy among all pill users (153).

For many women throughout the world, effectively using family planning can save not only their own lives but also their children's. The one million or more children who are left motherless each year due to maternal mortality are 3 to 10 times more likely to die within two years than children who live with both parents (229).

Some women who become pregnant while taking the pill have abortions. In England 17% of abortion-seekers were using the pill when they became pregnant (173). In Australia a survey of over 2,000 women who had abortions in 1992 found that 14% were using the pill when they conceived (235). Where abortion is unsafe, its consequences include nearly 80,000 maternal deaths annually and hundreds of thousands of disabilities. In fact, in some countries complications of unsafe abortion causes more maternal deaths than any other single factor (243). More effective pill use can avert much morbidity and mortality among women of reproductive age.