The conventional wisdom has it that an epidemic of teen pregnancy is today ruining the lives of young women and their children and perpetuating poverty in America. In polite circles, people speak regretfully of "babies having babies." Other Americans are more blunt. "I don't mind paying to help people in need," one angry radio talk show host told Michael Katz, a historian of poverty, "but I don't want my tax dollars to pay for the sexual pleasure of adolescents who won't use birth control."