What happens to contraceptive use after injectables are introduced? An analysis of 13 countries.

Although the introduction of a new method is generally hailed as a boon to contraceptive prevalence, uptake of new methods can reduce the use of existing methods. It is important to examine changing patterns of contraceptive use and method mix after the introduction of new methods. Demographic and Health Survey data from 13 countries were used to analyze changes in method use and method mix after the introduction of the injectable in the early 1990s. Subgroup analyses were conducted among married women who reported wanting more children, but not in the next two years (spacers), and those who reported wanting no more children (limiters). Modern method use and injectable use rose for each study country. Increases in modern method use exceeded those in injectable use in all but three countries. Injectable use rose among spacers, as well as among limiters of all ages, particularly those younger than 35. In general, the increase in injectable use was partially offset by declines in use of other methods, especially long-acting or permanent methods. Family planning programs could face higher costs and women could experience more unintended pregnancies if limiters use injectables for long periods, rather than changing to longer acting and permanent methods, which provide greater contraceptive efficacy at lower cost, when they are sure they want no more children.