Births: final data for 2003.

OBJECTIVES This report presents 2003 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 characteristics (medical risk factors, weight gain, and tobacco and alcohol use); medical care utilization by pregnant women (prenatal care, obstetric procedures, complications of labor and/or delivery, attendant at birth, and method of delivery); and infant characteristics (period of gestation, birthweight, Apgar score, abnormal conditions, 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 4.09 million births that occurred in 2003 are presented. Denominators for population-based rates are derived from the U.S. 2000 census. RESULTS In 2003 there were 4,089,950 live births reported in the United States, 2 percent more than the number in 2002. The crude birth rate (CBR) and general fertility rate (GFR) rose slightly. Childbearing among teenagers declined for the 12th straight year to another historic low. Birth rates for women aged 20-24 years also declined, whereas rates for women aged 25-44 years increased 2-6 percent, reaching highs not reported since the mid- to late 1960s. All measures of unmarried childbearing increased considerably in 2003, but smoking during pregnancy continued to decline. Timely initiation of prenatal care improved slightly. The cesarean delivery rate jumped another 5 percent to another all-time high, and the rate of vaginal birth after previous cesarean dropped 16 percent, an all-time low. Key measures of birth outcome-the percentages of preterm and low birthweight (LBW) births-rose. The twinning rate increased, but the rate of triplet and higher order multiple births was essentially stable.