CONTEXT: The reproductive choices made by young women and men have an enormous impact on their health, schooling, employment prospects and overall transition to adulthood. As the largest cohort of young people in history enter their childbearing years, their reproductive behavior will determine the growth and size of the world's population for decades to come.

METHODS: Demographic and Health Survey data from more than 40 countries were used to examine the proportions of 15–19-year-old women who are currently married or are unmarried but sexually active; their rates of contraceptive adoption, current use, discontinuation, method switching and contraceptive failure; trends in these indicators; and comparisons with older women.

RESULTS: In many countries, the proportion of adolescent women using contraceptives increased substantially over the last two decades; prevalence among adolescents increased faster than among older women. Greater proportions of adolescents than of older women discontinued using a contraceptive method within a year or experienced contraceptive failure.

CONCLUSIONS: Adolescent contraceptive use is growing, and compared with adult use, is characterized by shorter periods of consistent use with more contraceptive failure and more stopping for other reasons. Use through the reproductive years is likely to grow, fueled further by growth in the numbers of young people. An expanded demand for contraceptive supplies, services and information can be expected to challenge the preparedness, capacity and resources of existing family planning programs and providers.