The crude birth rate in 2004 was 14.0 births per 1000 population, the second lowest ever reported for the United States. The number of births and the fertility rate (66.3) increased slightly (by <1%) from 2003 to 2004. Fertility rates were highest for Hispanic women (97.7), followed by Asian or Pacific Islander (67.2), non-Hispanic black (66.7), Native American (58.9), and non-Hispanic white (58.5) women. The birth rate for teen mothers continued to fall, dropping 1% from 2003 to 2004 to 41.2 births per 1000 women aged 15 to 19 years, which is another record low. The teen birth rate has fallen 33% since 1991; declines were more rapid for younger teens aged 15 to 17 (43%) than for older teens aged 18 to 19 (26%). The proportion of all births to unmarried women is now slightly higher than one third. Smoking during pregnancy declined slightly from 2003 to 2004. In 2004, 29.1% of births were delivered by cesarean delivery, up 6% since 2003 and 41% since 1996 (20.7%). The primary cesarean delivery rate has risen 41% since 1996, whereas the rate of vaginal birth after a previous cesarean delivery has fallen 67%. The use of timely prenatal care was 84.0% in both 2003 and 2004. The percentage of preterm births rose to 12.5% in 2004 from 10.6% in 1990 and 9.4% in 1981. The percentage of low birth weight births also increased to 8.1% in 2004, up from 6.7% in 1984. Twin birth rate and triplet/+ birth rates increased by 1% and <1%, respectively, from 2002 to 2003. Multiple births accounted for 3.3% of all births in 2003. The infant mortality rate was 7.0 per 1000 live births in 2002 compared with 6.8 in 2001. The ratio of the infant mortality rate among non-Hispanic black infants to that for non-Hispanic white infants was 2.4 in 2002, the same as in 2001. The United States continues to rank poorly in international comparisons of infant mortality. Expectation of life at birth reached a record high of 77.6 years for all gender and race groups combined. Death rates in the United States continue to decline, with death rates decreasing for 8 of the 15 leading causes. Death rates for children < or =19 years of age declined for 7 of the 10 leading causes in 2003. The death rates did not increase for any cause, and rates for heart disease, influenza, and pneumonia and septicemia did not change significantly for children as a group. A large proportion of childhood deaths, however, continue to occur as a result of preventable injuries.