Abortion rates have dropped steadily since the 1980s, from a peak of 29.3 abortions per 1,000 women in 1981 to 19.4 in 2005. But behind this general decrease are striking changes in the demographics of abortion. Compared to 30 years ago, women having abortions today are older and more likely to be mothers and minorities, according to a study released Tuesday by the nonprofit, nonpartisan Guttmacher Institute.

In fact, teens saw a bigger drop in abortion rate than any other demographic over the past 30 years. From 1974 to 1989, women aged 18-19 had the highest

abortion rate among all age groups, varying from 32 to 62 per 1,000 women. In 2004, the latest year for which data is available, the abortion rate was 20.5.

"We've done a great job educating kids about the risks of sexual behavior and proper contraceptive use," says Jones. So it's not the kids that researchers are most worried about--it's the age groups above them.