The fertility rate measures the number of births per 1,000 women between the ages of 15 and 44 occurring in a particular year; birth rates refer to this measure within particular age groups. Tracking trends in fertility and birth rates is essential in planning for the current and future needs of multiple generations. Sustained high fertility rates lead to disproportionately large populations of young dependents, driving demand for supports for young families, for additional schools, and for affordable child care., For example, during the baby boom period (births from 1946 to 1964), unanticipated high fertility rates caught communities unprepared, and without the facilities needed to accommodate rapidly increasing numbers of school-age children. On the other hand, sustained low fertility rates can lead to an aging population and, in the long run, may place burdens on the economy and social services, because the pool of younger workers responsible for supporting the elderly accounts for a relatively smaller share of the population.
Tracking age-specific and race/ethnicity-specific trends in fertility and birth rates also provides information on the divergent needs of different population groups. For example, high teen birth rates among Hispanics in recent years alerted groups working in adolescent pregnancy prevention to anticipate the particular needs of this population. At the other end of the continuum, increasing fertility among older mothers may be related to an increased risk of pregnancy complications, and to elevated risk for infant mortality and presence of autism spectrum disorders.
Fertility rates in the United States declined sharply between the baby boom years of the 1950s and early 1960s, and 1976 (118 and 65 births per 1,000 women of childbearing age for 1960 and 1976, respectively). Since the 1970s, fertility rates have been relatively stable, varying between 63 and 71 births per 1,000 women. There were small peaks in 1990 and 2007, but rates have since gone down, and are the lowest in recent history, standing at 63 per 1,000 women in 2014. (Figure 1) The total number of births in 2007—4,317,119—was the highest ever registered in the United States, though that annual number has since fallen.
Women in the middle of their childbearing years have the highest birth rates. Specifically, rates are highest for women ages 25 to 29 (at 106 births per 1,000 in 2014), followed by those for women ages 30 to 34 (at 101 births per 1,000), and women ages 20 to 24 (79 births per 1,000). (Figure 2) Beginning in 2003, the birth rate for women ages 35 to 39 has been higher than that for young women ages 15 to 19—a marked change from previous years. Birth rates for women ages 30-34, 35-39, 40-44, and 45-54 increased between 2010 and 2014, while birth rates for younger women decreased. Declines were greatest for women between the ages of 15 and 24 (falling by 29 percent for women 15 to 19, and by 12 percent for women 20 to 24). (Appendix 1) Birth rates for women over 45, and for those under 15, were below one birth per 1,000 in 2014. (Figure 2)
In 2014, fertility rates were highest for Hispanic women (72 per thousand), followed by rates for black (65 per thousand), Asian (61 per thousand), white (60 per thousand), and American Indian women (45 per thousand). (Appendix 1) Among teens (ages 15-19), declines were seen in all groups, and for Hispanic teens the birth rate reached an historic low.
Among Hispanic women in 2013 (the latest data available), Central and South American women had the highest fertility rate, at 94 births per 1,000. Mexican women also had a relatively high fertility rate (68 births per 1,000), while Puerto Rican and Cuban women had lower fertility rates (58 and 48 births per 1,000, respectively). (Appendix 1)
State estimates for fertility rates and number of births by selected demographic characteristics for 2014 are available from Births: Final data for 2014. National Vital Statistics Reports, 64(1). Hyattsville, MD: National Center for Health Statistics. (Tables 10, 11, and 12)
Birth and fertility rates in greater demographic detail are available by state from Trends in characteristics of births by state: United States, 1990, 1995, and 2000-2002. National Vital Statistics Reports, 52(19). (See table 3).
International crude birth rates and total fertility rates** are available from the 2015 World Population Data Sheet of the Population Reference Bureau. (2011). Washington, DC: Population Reference Bureau.
**Note: The international definitions of crude birth rates and total fertility rates differ substantially from the birth rates and fertility rates referenced in this indicator. For this reason, these international estimates are not comparable to the estimates presented here. Crude birth rates are defined as births per 1,000 of the total population (including all ages, races, and both genders). Total fertility rates are defined as the average number of children a woman would have if the current age-specific birth rates did not change during her childbearing years (usually between ages 15-49). For more details about these definitions, please see the publication listed above.
International total fertility rates are also available from the United Nations Population Division and World Health Organization.
The fertility rate is defined by the National Center for Health Statistics as the total number of live births per 1,000 women aged 15 to 44 years. These rates are based on the most recent population estimates from the Census Bureau. Birth rates are different from fertility rates in that the denominator is not all women aged 15 to 44, but rather a specific age group.
For more detailed information, see Table 3 and the Technical Notes section of “Births: Final data for 2014“.
Data for 1990-2014: Hamilton, B. E., Martin, J. A., Osterman, M. J. K., Curtin, S. C., & Mathews, T. J. (2015). Births: Final data for 2014. National Vital Statistics Reports, 64(12). Hyattsville, MD: National Center for Health Statistics. Available at http://www.cdc.gov/nchs/data/nvsr/nvsr64/nvsr64_12.pdf. Tables 1, 4, and 5.
Data for 1950 through 1985: National Center for Health Statistics. (2002). Health, United States, 2002. With Chartbook on Trends in the Health of Americans. Hyattsville, Maryland. Table 3.
National Vital Statistics System birth data
|Central and South American||–||–||–||–||102.7||89.1||85.1||90.5||97.1||96.3||94.9||94.4||–|
|Asian or Pacific Islander||–||–||–||73.2||69.6||62.6||65.8||63.0||59.2||59.9||62.2||59.2||60.7|
|1The total number includes births to women of all ages, 15-44 years. The rate shown for all ages is the general fertility rate, which is defined as the total number of births per 1,000 women aged 15-44 years. Age-specific birth rates are defined as the total number of births per 1,000 women in a specific age group (between ages 15 and 44).
2Data for estimates before 1980 are based on the race/ethnicity of the child, from 1980 on estimates are based on the race/ethnicity of the mother. Before 1980 data for the mother’s marital status was estimated for the United States from data for registration areas in which marital status of mother was reported. For 1980 on, data for States in which the mother’s marital status was not reported were inferred from other items on the birth certificate and included with data from the reporting States.
3Includes all persons of Hispanic origin of any race.
4Birth rates computed by relating births to women ages 45-54 years to women ages 45-49 years.
Sources: Data for 1950 through 1985: National Center for Health Statistics. (2002). Health, United States, 2002. With Chartbook on Trends in the Health of Americans. Hyattsville, Maryland. Table 3. Data for 1990-2014: Hamilton, B. E., Martin, J. A., Osterman, M. J. K., Curtin, S. C., & Mathews, T. J. (2015). Births: Final data for 2014. National Vital Statistics Reports, 64(12). Hyattsville, MD: National Center for Health Statistics. http://www.cdc.gov/nchs/data/nvsr/nvsr64/nvsr64_12.pdf. Tables 1, 4, and 5.
Additional years of data are available in the excel spreadsheet.
Weeks, J. R. (2002). Population: An introduction to concepts and issues (8th edition). Belmont, CA: Wadsworth Publishing Company.
Coale, Ansley J. (1987). How a population ages or grows younger. In S. W. Menard and E. W. Moen (eds.), Perspectives on Population: An Introduction to Concepts and Issues. Pp. 365-369. Oxford: Oxford University Press.
Vexler, E. J., and Suellentrop, K. (2006). Bridging two worlds: How teen pregnancy prevention programs can better serve Latino youth. National Campaign to Prevent Teen Pregnancy. Retrieved from http://www.thenationalcampaign.org/resources/pdf/pubs/BridgingEng_FINAL.pdf
Luke, B. & Brown, M. B. (2007). Elevated risks of pregnancy complications and adverse outcomes with increasing maternal age. Human Reproduction, 22(5), 1264-1272; Croen, L. A., Najjar, D. V., Fireman, B., & Grether, J. K. (2007). Maternal and paternal age and risk of autism spectrum disorders. Archives of Pediatric & Adolescent Medicine, 161, 334-340.
Hamilton, B. E., Martin, J. A., Osterman, M. J. K., Curtin, S. C., & Mathews, T. J. (2015). Births: Final data for 2014. National Vital Statistics Reports, 64(12). Hyattsville, MD: National Center for Health Statistics. Available at http://www.cdc.gov/nchs/data/nvsr/nvsr64/nvsr64_12.pdf. Table 1.
Hispanics may be any race. Estimates for whites and blacks in this report do not include Hispanics.
Martin J. A., Hamilton B. E., Osterman, M. J. K., Curtin, S. C., & Mathews T. J. (2015). Op cit. Table A.
Child Trends Databank. (2016). Fertility and birth rates. Available at: http://www.childtrends.org/?indicators=fertility-and-birth-ratesLast updated: October 2016