U.S. pregnancy rates declined about 10 percent each for married and unmarried women since 1990, researchers say. Sally Curtin, Joyce Abma and Stephanie Ventura of the National Center for Health Statistics, part of the Centers for Disease Control and Prevention, and Stanley Henshaw of the Guttmacher Institute found the U.S. pregnancy rate in 2009 was 102.1 per 1,000 women ages 15-44 -- the lowest level in 12 years. Only the 1997 rate of 101.6 was lower in the last 30 years. Rates for women age 30 and younger fell during 1990-2009, rates for women age 30 and older increased and rates for teenagers reached historic lows in 2009, the report said. From 1990-2009, birth rates fell 51 percent for non-Hispanic white and non-Hispanic black teenagers and 40 percent for Hispanic teenagers. The birth rate for married women was 72 percent higher than the rate for unmarried women; the abortion rate for unmarried women was almost five times higher than the rate for married women, the report said. The data on pregnancy outcomes were calculated using data from the National Vital Statistics System, the Abortion Surveillance System, the Guttmacher Institute and the National Survey of Family Growth.