Births: preliminary data for 2004.

OBJECTIVES: This report presents preliminary data for 2004 on births in the United States. U.S. data on births are shown by age, race, and Hispanic origin of mother. Data on marital status, tobacco use, prenatal care, cesarean delivery, preterm births, and low birthweight (LBW) are also presented. METHODS: Data in this report are based on 99.1 percent of births for 2004. The records are weighted to independent control counts of all births received in State vital statistics offices in 2004. Comparisons are made with 2003 data. RESULTS: The crude birth rate declined 1 percent to 14.0 births per 1,000 population. The fertility rate, however, rose slightly to 66.3 births per 1,000 women aged 15-44 years. Birth rates for teenagers 15-19 years declined modestly. The rate in 2004 was 41.2 births per 1,000 females aged 15-19 years, 1 percent lower than in 2003. Rates declined 1 percent each for teenagers 15-17 and 18-19 years. The rate for 10-14 year-olds increased slightly. The birth rate for women aged 20-24 years declined 1 percent to 101.8, a record low for the Nation. The rate for women aged 25-29 years remained essentially unchanged at 115.5 per 1,000. The birth rate for women aged 30-34 years rose less than 1 percent to 95.5 per 1,000, whereas the rates for women aged 35-39 and 40-44 years increased 3 to 4 percent each. The rate for women aged 45-49 years rose to 0.6 per 1,000. Childbearing by unmarried women rose to a record high of almost 1.5 million births in 2004, a 4-percent increase from 2003. The proportion of all births to unmarried women increased to 35.7 percent. Smoking during pregnancy declined slightly in 2004, to 10.2 percent of mothers in the 40-State reporting area. There was no improvement in timely receipt of prenatal care. In 2004, 83.9 percent of mothers in the 41-State reporting area began care in the first trimester. A record high cesarean delivery rate was reported in 2004, at 29.1 percent of all births, a 6-percent increase from 2003. The primary cesarean rate rose 8 percent, whereas the rate of vaginal birth after cesarean delivery declined 13 percent. Preterm and LBW rates each increased in 2004. More than 500,000 infants were born preterm, a rate of 12.5 percent. The LBW rate increased to 8.1 percent.     

Births: preliminary data for 2000.

OBJECTIVES: This report presents preliminary data for 2000 on births in the United States. U.S. data on births are shown by age, race, and Hispanic origin of mother. Data on marital status, prenatal care, cesarean delivery, and low birthweight are also presented. METHODS: Data in this report are based on more than 96 percent of births for 2000. The records are weighted to independent control counts of births received in State vital statistics offices in 2000. Comparisons are made with 1999 final data. RESULTS: The number of births rose 3 percent between 1999 and 2000. The crude birth rate increased to 14.8 per 1,000 population in 2000, 2 percent higher than the 1999 rate. The fertility rate rose 3 percent to 67.6 per 1,000 women aged 15-44 years between 1999 and 2000. The birth rate for teenagers, which has been falling since 1991, declined 2 percent in 2000 to 48.7 births per 1,000 females aged 15-19 years, another historic low. The rate for teenagers 15-17 years fell 4 percent, and the rate for 18-19 year olds was down 1 percent. Since 1991, rates have fallen 29 percent for teenagers 15-17 years and 16 percent for teenagers 18-19 years. Birth rates for all of the older age groups increased for 1999-2000: 1 percent among women aged 20-24 years, 3 percent for women aged 25-29 years, and 5 percent for women in their thirties. Rates for women aged 40-54 years were also up for 2000. The birth rate for unmarried women increased 2 percent to 45.2 births per 1,000 unmarried women aged 15-44 years in 2000, but was still lower than the peak reached in 1994. The number of births to unmarried women was up 3 percent, the highest number ever reported in the United States. However, the number of births to unmarried teenagers declined. The proportion of women who began prenatal care in the first trimester of pregnancy (83.2 percent) did not improve for 2000, nor did the rate of low birthweight (7.6 percent). The total cesarean rate rose for the fourth consecutive year to 22.9 percent, the result of both a rise in the rate of primary cesarean deliveries and a decline in the rate of vaginal births after previous cesarean delivery.     

Births: preliminary data for 2001.

OBJECTIVES: This report presents preliminary data for 2001 on births in the United States. U.S. data on births are shown by age, race, and Hispanic origin of mother. Data on marital status, prenatal care, cesarean delivery, and low birthweight are also presented. METHODS: Data in this report are based on more than 96 percent of births for 2001. The records are weighted to independent control counts of all births received in State vital statistics offices in 2001. Comparisons are made with 2000 final data. RESULTS: The number of births, the crude birth rate, and the fertility rate all declined slightly between 2000 and 2001. The number of births was down by less than 1 percent, the crude birth rate declined 1 percent to 14.5 per 1,000 population, and the fertility rate was down slightly to 67.2 births per 1,000 women aged 15-44 years. Teenagers were less likely to give birth in 2001; the teen birth rate continued to fall, dropping 5 percent between 2000 and 2001 to 45.9 births per 1,000 females aged 15-19 years, another record low. The teen birth rate has fallen 26 percent since 1991. The birth rate for teenagers 15-17 years fell 8 percent, and the rate for teenagers 18-19 years was down 4 percent for 2000-2001. Since 1991 rates have fallen 35 percent for teenagers 15-17 years, and 20 percent for teenagers 18-19 years. Birth rates for women aged 20-24 declined by 2 percent, whereas rates for women 25-44 years increased. Childbearing among women aged 40-54 years was stable. The birth rate for unmarried women decreased modestly to 44.9 births per 1,000 unmarried women 15-44 years in 2001, still remaining below the peak reached in 1994. The number of births to unmarried women was up very slightly, but births to unmarried teens were down. The proportion of women who began prenatal care in the first trimester of pregnancy improved slightly to 83.4 percent, but the rate of low birthweight held at 7.6 percent. The total cesarean delivery rate jumped 7 percent between 2000 and 2001 to 24.4 percent of all births, the highest level ever reported from this data source; the primary rate of cesarean deliveries rose 5 percent, and the rate of vaginal births after previous cesarean delivery tumbled 20 percent.     

Births: preliminary data for 2002.

OBJECTIVES: This report presents preliminary data for 2002 on births in the United States. U.S. data on births are shown by age, race, and Hispanic origin of mother. Data on marital status, prenatal care, cesarean delivery, preterm births, and low birthweight are also presented. METHODS: Data in this report are based on nearly 98 percent of births for 2002. The records are weighted to independent control counts of all births received in State vital statistics offices in 2002. Comparisons are made with 2001 final data. RESULTS: The crude birth rate was 13.9 per 1,000 population in 2002, a decrease of 1 percent from 2001 (14.1). This is the lowest birth rate reported for the United States since national data have been available. The fertility rate was also down 1 percent in 2002 to 64.8 births per 1,000 women aged 15-44 years. Since 1990, this rate has declined 9 percent. The birth rate for teenagers continued to decline in 2002, dropping 5 percent to 42.9 births per 1,000 women aged 15-19 years. The teenage birth rate has dropped 28 percent since 1990. The rate for younger teenagers 15-17 years fell 6 percent from 24.7 per 1,000 in 2001 to 23.2 in 2002. The rate for older teenagers 18-19 years declined 4 percent from 76.1 per 1,000 in 2001 to 72.7 in 2002. Since 1990, the rate for teenagers 15-17 years has fallen 38 percent and the rate for teenagers 18-19 years, 18 percent. The birth rate for women aged 20-24 years declined by 3 percent to 103.5 per 1,000 in 2002 compared with 2001, whereas the rate for women aged 25-29 years was essentially unchanged (113.6). The birth rate for women aged 30-34 years decreased slightly from 91.9 per 1,000 in 2001 to 91.6 in 2002. Birth rates for women aged 35-39 years and 40-44 years continued to rise, increasing 2 percent for both. Childbearing among women over 45 years of age was unchanged. The birth rate for unmarried women was down slightly in 2002 to 43.6 births per 1,000 unmarried women aged 15-44 years. The number of births to unmarried women increased by 1 percent in 2002; however births to unmarried teenagers declined by 4 percent. Prenatal care utilization continued to slowly but steadily improve; 83.8 percent of women began prenatal care in the first trimester of pregnancy in 2002 compared with 83.4 in 2001. More than one fourth of all births (26.1 percent) were cesarean deliveries in 2002, the highest rate ever reported in the United States; the primary cesarean rate jumped 7 percent to 18 percent and the rate of vaginal births after previous cesarean delivery plummeted 23 percent to 12.7 percent (figure 1). Preterm (12.0 percent) and low birthweight (7.8 percent) rates were up slightly for 2002. The low birthweight rate is the highest reported in more than three decades.     

Births: preliminary data for 2003.

OBJECTIVES: This report presents preliminary data for 2003 on births in the United States. U.S. data on births are shown by age, race, and Hispanic origin of mother. Data on marital status, tobacco use, prenatal care, cesarean delivery, preterm births, and low birthweight are also presented. METHODS: Data in this report are based on nearly 99 percent of births for 2003. The records are weighted to independent control counts of all births received in State vital statistics offices in 2003. Comparisons are made with 2002 final data. RESULTS: The crude birth rate rose to 14.1 births per 1000 population in 2003, an increase of 1 percent from 2002 (13.9). The fertility rate also rose in 2003 by 2 percent to 66.1 births per 1000 women aged 15-44 years. Since 1994, the rate has ranged from 63.6 to 66.1. The birth rate for teenagers continued to decline in 2003 to 41.7 births per 1000 women aged 15-19 years, 3 percent lower than in 2002. Rates fell for teenagers in all race and Hispanic origin groups, in many cases marking new record lows for the Nation. Birth rates for teenagers 15-17 and 18-19 years continued to steadily decline. The rate for ages 15-17 was 22.4 per 1000 in 2003, down 3 percent from 2002 and 42 percent from 1991, the recent peak. The rate for older teenagers 18-19 years in 2003 was 70.8 per 1000, also 3 percent lower than in 2002 and 25 percent lower than in 1991. The birth rates for women in their twenties were 102.6 per 1000 for women aged 20-24 years and 115.7 for women aged 25-29 years, a decrease of 1 percent and an increase of 2 percent, respectively, compared with 2002. The birth rate for women aged 30-34 years increased 4 percent to 95.2 births per 1000 women compared with 2002. The rate rose 6 percent for women aged 35-39 years, between 2002 and 2003, and 5 percent for women aged 40-44 years. The rate for women aged 45-49 years remained unchanged. The birth rate for unmarried women increased by 3 percent in 2003, from 43.7 to 44.9 per 1000 unmarried women aged 15-44 years. The proportion of births to unmarried women also increased in 2003 to 34.6 percent, compared with 34.0 percent in 2002. The proportion of mothers smoking during pregnancy continued to steadily decline in 2003, from 11.4 percent in 2002 to 11.0 percent. The percent of women who received prenatal care within the first 3 months of pregnancy edged upward for 2003, to 84.1 percent, compared with 83.7 percent in 2002. In 2003, 27.6 percent of all births were delivered by cesarean delivery, a marked rise of 6 percent over the 2002 level, and one-third higher than that for 1996. The primary cesarean rate also rose 6 percent between 2002 and 2003 while the rate of vaginal birth after previous cesarean (VBAC) dropped by 16 percent. Preterm and low birthweight rates both rose between 2002 and 2003. The preterm rate increased from 12.1 to 12.3 and low birthweight rate rose from 7.8 to 7.9 percent.     

Births: preliminary data for 1999.

OBJECTIVES: This report presents preliminary data for 1999 on births in the United States. U.S. data on births are shown by age, race, and Hispanic origin of mother. Data on marital status, prenatal care, cesarean delivery, and low birthweight are also presented. METHODS: Data in this report are based on more than a 97-percent sample of births for 1999. The records are weighted to independent control counts of births received in State vital statistics offices in 1999. Comparisons are made with 1998 final data. RESULTS: The crude birth rate in 1999 was 14.5 per 1,000 population, a slight decline from 1998 (14.6), returning to the level observed in 1997. However, the fertility rate, which is limited to women aged 15-44 years, was 65.8 in 1999, a slight increase over the rate for 1998 (65.6). The birth rate for teenagers continued to decline for 1998-99, dropping 3 percent to 49.6 births per 1,000 females aged 15-19 years. The 1999 rate for teenagers is 20 percent lower than the recent high point in 1991. The rate for young teenagers 15-17 years fell 6 percent, and the rate for teenagers 18-19 years declined 2 percent. Since 1991, rates have fallen 26 percent for teenagers 15-17 years, and 15 percent for teenagers 18-19 years. Birth rates for women aged 20-24 years declined slightly between 1998 and 1999 whereas the rate for women aged 25-29 years rose 2 percent. Birth rates for women in their thirties and forties continued their long increase. Rates for women in their thirties increased 2 to 3 percent and were the highest in three decades. The birth rate for women aged 40-44 years was the highest level reported since 1970. The birth rate for unmarried women in 1999 was 43.9 per 1,000, 1 percent lower than in 1998 and 6 percent lower than the peak level reported for 1994 (46.9). However, the number of births to unmarried women was up about 1 percent due to the continued increase in the number of unmarried women of childbearing age. The rate of prenatal care utilization continued to improve. The total cesarean rate increased 4 percent between 1998 and 1999 and continued a 3-year rise. The low birthweight rate remained unchanged at 7.6 percent.     

Trends in twin and triplet births: 1980-97.

This report presents data from U.S. birth certificates on the numbers and rates of twin and triplet and other higher order multiple births for 1980-97. Over the study period, the number of twin births rose 52 percent (from 68,339 to 104,137) and triplet and other higher order multiple births (heretofore referred to as "triplet/+") climbed 404 percent (from 1,337 to 6,737 births). Comparable but less pronounced rises were observed in twin and triplet/+ birth rates. Growth in twin and triplet/+ birth rates was most marked among women aged 30 years and over. Between 1980-82 and 1995-97, the twin rate rose 63 percent for women aged 40-44 years, and soared nearly 1,000 percent for women 45-49 years. (As one result, there were more twins born to women 45-49 years of age in 1997, than during the entire decade of the 1980's.) The triplet/+ birth rate rose nearly 400 percent for women in their thirties and exploded by more than 1,000 percent for women in their forties. The extraordinary rise in multiple births resulted in a shift in age-specific patterns, and the highest twin and triplet/+ birth rates now are for women 45-49 years of age. Historical differences in twinning rates between non-Hispanic white and black mothers have been largely eliminated (28.8 per 1,000 non-Hispanic white compared with 30.0 for black women). Non-Hispanic white women were more than twice as likely as non-Hispanic black or Hispanic women to have a triplet/+ birth. Rates of low birthweight, very low birthweight, and infant mortality were 4 to 33 times higher for twins and triplet/+ compared with singleton births. The risk for these adverse outcomes was lowest for twins and triplet/+ born to women 35-44 years of age. Twin birth rates for Massachusetts and Connecticut were at least 25 percent higher than the U.S. rate; triplet/+ rates for Nebraska and New Jersey were twice the national level.     

Estimated pregnancy rates for the United States, 1990-2000: an update.

OBJECTIVES: This report presents detailed pregnancy rates for 1990-2000, updating a national series of rates extending since 1976. METHODS: Tabular data on pregnancy rates by age, race, and Hispanic origin, and by marital status are presented and briefly described. RESULTS: In 2000 an estimated 6,401,000 pregnancies resulted in 4.06 million live births, 1.31 million induced abortions, and 1.03 million fetal losses. The 2000 pregnancy rate of 104.0 pregnancies per 1,000 women aged 15-44 years is 10 percent lower than the 1990 peak of 115.6. The teenage pregnancy rate dropped 27 percent during 1990-2000, reaching an historic low of 84.5 pregnancies per 1,000 women aged 15-19 years. Rates for younger teenagers declined relatively more than for older teenagers.     

Trends in low birth weight infants and changes in Baltimore's childbearing population, 1972–77

Linked birth and death records provided the population for a study of trends in low birth weight (LBW) rates in Baltimore between 1972 and 1977 and of the effect of changes in the characteristics of the childbearing population on these trends. The impact of shifts in the birth weight distribution on neonatal mortality rates was also investigated. Trends were analyzed for unstandardized LBW rates as well as for rates standardized on the distributions of maternal age, education, gravidity, prior pregnancy losses, and marital status.Between 1972 and 1977, the 1,500 and 2,000 gm rates rose significantly by approximately 1 infant per 1,000 live births per year among whites and 2 infants per 1,000 live births among nonwhites. Despite declines in rates for most weights, the effect of these increases was a rise in neonatal mortality rates for both races, but especially for nonwhites.The population of women delivering in Baltimore in 1977 became slightly older, slightly more educated, and of higher gravidity than in 1972, but these changes had little impact on yearly fluctuations in LBW rates. In contrast, increases in births to unmarried women and to women with at least one prior pregnancy loss were related to rising LBW rates. For both races, standardization on marital status and prior pregnancy losses diminishes the increase in the LBW rate over the study period, especially when standardization is performed simultaneously for both variables. These findings hold within maternal age, education, and gravidity groups. However, the LBW rates for nonwhite teenage mothers and for nonwhite women with 12 years of less education increased significantly over the study period, regardless of standardization.     

A portrait of American women who obtain abortions

In 1981, as in 1980, most abortions in the United States were obtained by young women, unmarried women and white women, and were performed in the first eight weeks following the last menstrual period (approximately six weeks after conception). The proportion of abortions obtained by unmarried women has increased slightly, and the fraction obtained by teenagers has decreased, mainly because of shifts in the distribution of these groups in the population. The percentage of abortions that are repeat procedures has increased, representing more than one-third of all abortions. The increase is due largely to the rise in the number of women who have had a first abortion, and who are, therefore, exposed to the risk of having a second procedure. Eighty-five percent of all abortions are performed by vacuum aspiration. Dilatation and evacuation is the method used in two-thirds of abortions performed more than 12 weeks past the last menstrual period, and in nine out of 10 abortions that are performed between the 13th and the 15th week. About three percent of women aged 15-44 obtained abortions in 1981, and 26 percent of pregnancies were terminated by abortion--the same fractions as in 1980. About six percent of 18-19-year-olds had abortions--the highest rate of any age-group. The abortion rate (the number of abortions per 1,000 women aged 15-44) and ratio (the number of abortions per 100 live births and abortions) are much higher for unmarried than for married women.(ABSTRACT TRUNCATED AT 250 WORDS)     

Characteristics of U.S. women having abortions, 1982-1983

In 1982 and 1983, as in previous years, the majority of abortions in the United States were obtained by young women (62 percent), white women (70 percent) and unmarried women (81 percent). Half of all abortions were performed eight or fewer weeks after the last menstrual period, and 91 percent, at 12 weeks or earlier. The proportion of abortions that were repeat procedures continued to rise, to 37 percent in 1982 and 39 percent in 1983. The rate of abortion, 29 per 1,000, has remained essentially the same since 1981. Women aged 18-19 continue to have the highest abortion rate of any age-group (60 per 1,000). While most abortions are obtained by white women, the nonwhite abortion rate is more than twice that of whites. Thirty percent of all pregnancies were terminated by abortion in 1983, the same proportion as in 1982 and 1981. The highest abortion ratios are found among unmarried women (63 percent), women 40 and older (51 percent), teenagers (42 percent) and nonwhites (40 percent). Teenage nonwhites and whites have about the same abortion ratios. After rising during the 1970s, the adolescent pregnancy rate peaked around 1980-1981 and fell slightly in 1982-1983. The relative differentials between the pregnancy, birth and abortion rates of nonwhite and white teenagers narrowed somewhat between 1978 and 1981, but then widened slightly between 1981 and 1983.     

Trends in pregnancy rates for the United States, 1976-97: an update.

OBJECTIVES: This report presents detailed pregnancy rates for 1996 and 1997 to update a recently published comprehensive report on pregnancies and pregnancy rates for U.S. women. METHODS: Tabular and graphic data on pregnancy rates by age, race, and Hispanic origin, and by marital status are presented and described. RESULTS: In 1997 an estimated 6.19 million pregnancies resulted in 3.88 million live births, 1.33 million induced abortions, and 0.98 million fetal losses. The 1997 pregnancy rate of 103.7 pregnancies per 1,000 women aged 15-44 years is the lowest recorded since 1976 (102.7), the first year for which a consistent series of national pregnancy rates is available. The 1997 rate was 10 percent lower than the peak rate in 1990 (115.6). The teenage pregnancy rate dropped steadily through 1997, falling to a record low of 94.3 pregnancies per 1,000 teenagers 15-19 years, 19 percent below the 1990 level (116.3). Rates for younger teenagers declined more than for older teenagers.