Information about the socioeconomic characteristics of women obtaining abortions in the United States can help policymakers and family planning providers determine which groups of women need better access to contraceptive services. A representative sample of more than 10,000 women obtaining abortions from a stratified probability sample of 100 U.S. providers were surveyed in 2000-2001; survey data are used to examine the demographic characteristics of women who terminate pregnancies. This information, along with other national-level data, is used to estimate abortion rates and ratios for subgroups of women and examine recent changes in these measures. RESULTS. In 2000, 21 out of every 1,000 women of reproductive age had an abortion. Women who are aged 18-29, unmarried, black or Hispanic, or economically disadvantaged-including those on Medicaid-have higher abortion rates. The overall abortion rate decreased by 11% between 1994 and 2000. The decline was greatest for 15-17-year-olds, women in the highest income category, those with college degrees and those with no religious affiliation. Abortion rates for women with incomes below 200% of poverty and for women with Medicaid coverage increased between 1994 and 2000. The rate of decline in abortion among black and Hispanic adolescents was lower than that among white adolescents, and the abortion rate among poor teenagers increased substantially. Increased efforts are needed to help both adolescent women and adult women of all economic statuses avoid unintended pregnancies.