Repeat abortion in the United States: new insights.

The increasing numbers and proportions of repeat abortions in the United States, including higher order repeat abortions, can be adequately explained by the increasing numbers of women at risk and the heterogeneity of the population in regard to the need for and utilization of abortion services. The same factors, rather than a deterioration of contraceptive practice following abortion, explain the higher levels of repeat abortion rates compared with first abortion rates.