Births: final data for 2004.

OBJECTIVES: This report presents 2004 data on U.S. births according to a wide variety of characteristics. Data are presented for maternal demographic characteristics including age, live-birth order, race, Hispanic origin, marital status, and educational attainment; maternal lifestyle and health characteristics (medical risk factors, weight gain, and tobacco use); medical care utilization by pregnant women (prenatal care, obstetric procedures, characteristics of labor and/or delivery, attendant at birth, and method of delivery); and infant characteristics (period of gestation, birthweight, Apgar score, congenital anomalies, and multiple births). Also presented are birth and fertility rates by age, live-birth order, race, Hispanic origin, and marital status. Selected data by mother's state of residence are shown, as well as data on month and day of birth, sex ratio, and age of father. Trends in fertility patterns and maternal and infant characteristics are described and interpreted.

METHODS: Descriptive tabulations of data reported on the birth certificates of the 4.1 million births that occurred in 2004 are presented. Denominators for population-based rates are post-censal estimates derived from the U.S. 2000 census.

RESULTS: In 2004, 4,112,052 births were registered in the United States, less than 1 percent more than the number in 2003. The crude birth rate declined slightly; the general fertility rate increased by less than 1 percent. Childbearing among teenagers and women aged 20-24 years declined to record lows. Rates for women aged 25-34 and 45-49 years were unchanged, whereas rates for women aged 35-44 years increased. All measures of unmarried childbearing rose in 2004. Smoking during pregnancy continued to decline. No improvement was seen in the timely initiation of prenatal care. The cesarean delivery rate jumped 6 percent to another all-time high, whereas the rate of vaginal birth after previous cesarean fell by 13 percent. Preterm and low birthweight rates continued their steady rise. The twinning rate increased, but the rate of triplet and higher order multiple births was down slightly.