Today, May 3—in case you didn't know it—is "National Day To Prevent Teen Pregnancy." In the past decade, possibly no social program has been as dramatically effective as the effort to reduce teen pregnancy, and no results so uniformly celebrated. Between 1990 and 2000 the U.S. teen pregnancy rate plummeted by 28 percent, dropping from 117 to 84 pregnancies per 1,000 women aged 15-19. Births to teenagers are also down, as are teen abortion rates. It's an achievement so profound and so heartening that left and right are eager to take credit for it, and both can probably do so. Child-health advocates generally acknowledge that liberal sex education and conservative abstinence initiatives are both to thank for the fact that fewer teenagers are ending up in school bathroom stalls sobbing over the results of a home pregnancy test.