U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

Mean Age of Mothers is on the Rise: United States, 2000–2014

T.J. Mathews, M.S.; and Brady E. Hamilton, Ph.D.

Key findings

Data from the National 

Vital Statistics System

● The mean age of mothers has 

increased from 2000 to 2014 

for all birth orders, with age 

at first birth having the largest 

increase, up from 24.9 years in 

2000 to 26.3 years in 2014.

● Increases in the average age 

for all birth orders were most 

pronounced from 2009 to 2014.

● In 2014, Asian or Pacific 

Islander mothers had the oldest 

average age at first birth (29.5 

years), while American Indian 

or Alaska Native mothers had 

the youngest (23.1 years).

● Mean age at first birth 

increased in all states and the 

District of Columbia (D.C.) 

from 2000 to 2014, but D.C. 

(3.4 years) and Oregon had the 

largest increases (2.1 years).

A mother’s age at birth, and particularly the mean or “average” age when a 

mother has her first child, is of interest to researchers and the public. Mean age 

can affect the total number of births a mother has over a lifetime, which in turn 

impacts the composition and growth of the U.S. population. Age of mother is 

associated with a range of birth outcomes, such as multiple births and birth 

defects. An earlier report presented trends in mean age from 1970 to 2000 (1). 

This report updates the earlier report and presents trends in the mean age at 

first and higher birth orders by race and Hispanic origin of mother and by state 

from 2000 to 2014 (1).

Keywords: maternal age • race and Hispanic origin • birth order • National 

Vital Statistics System (NVSS)

What are the recent trends in average age of mothers in the 

United States?

● The mean age of first-time mothers increased 1.4 years, from 24.9 in 

2000 to 26.3 in 2014. While the mean age at first birth was fairly stable 

NCHS Data Brief ■ No. 232 ■ January 2016

Figure 1. Mean age, by birth order: United States, 2000–2014

SOURCE: CDC/NCHS, National Vital Statistics System. 

 
NCHS Data Brief ■ No. 232 ■ January 2016

■  2  ■

for the first half of this time period, greater increases were observed from 2009 (25.2 years) 

to 2014 (26.3 years) (Figure 1).

● Trends in mean age of mother for higher-order births were similar to those for first

births—that is, generally stable from 2000 to 2006, followed by greater increases from 2009 

to 2014. 

● Increases from 2000 to 2014 in average age for higher birth orders were less than those for 

first births, rising 1.4 years for first births, 1.0 years for second births, 0.8 years for

third- and fourth-order births, and 0.5 years for fifth- and higher-order births.

● As a result of the different rate of increases by birth order, the gap in the mean age between 

sequential birth orders has decreased. For example, the difference in the mean age at first 

birth compared with the mean age at second birth was 2.8 years in 2000 and 2.4 years in 

2014. 

How has the distribution of age at first birth changed? 

● The largest factor in the rise in mean age at first birth is the decline in the proportion of first 

births to mothers under age 20, down 42% from 2000 to 2014, or from approximately 1 in 4 

births to 1 in 7 (Figure 2). 

● From 2000 to 2014, the proportion of first births to women aged 30–34 rose 28% (from 

16.5% to 21.1%), and first births to women aged 35 and over rose 23% (from 7.4% to 

9.1%). 

Figure 2. Percentage of first births, by age of mother: United States, 2000–2014

SOURCE: CDC/NCHS, National Vital Statistics System. 

 
NCHS Data Brief ■ No. 232 ■ January 2016

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● The proportion of first births to mothers aged 20–24 was the same in 2000 and 2014, while 

the proportion of first births to mothers aged 25–29 increased 14%, from 24.3% in 2000 to 

27.7% in 2014.

Does the average age of first-time mothers differ by race and Hispanic 

origin?

● The mean age at first birth increased for all race and Hispanic origin groups from 2000 to 

2014. Increases ranged from 0.5 years for Cuban mothers to 1.9 years for non-Hispanic 

black mothers (Figure 3). 

● Asian or Pacific Islander (API) mothers had the oldest average age at first birth in 2000 

(27.8 years) and 2014 (29.5 years), while American Indian or Alaska Native (AIAN) women 

had the youngest average age at first birth (21.6 years in 2000 and 23.1 years in 2014). The 

difference in mean age at first birth among these groups was 6.4 years in 2014, up from 6.2 

years in 2000. 

Figure 3. Mean age at first birth, by race and Hispanic origin of mother: United States, 2000 and 2014

1

Includes persons of Hispanic and non-Hispanic origin.

SOURCE: CDC/NCHS, National Vital Statistics System.

 

 
NCHS Data Brief ■ No. 232 ■ January 2016

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● In 2014, the mean age at first birth for API (29.5 years), non-Hispanic white (27.0 years), 

Central and South American (26.5 years), and Cuban (27.0 years) mothers was higher 

than the average for all mothers (26.3 years). The mean age was lower than the average 

for Puerto Rican (24.1 years), non-Hispanic black (24.2 years), Mexican (23.7 years), and 

AIAN (23.1 years) mothers. 

Does average age of mother at first birth differ by geographic area over 

time?

● The average age of first-time mothers increased for all states and the District of Columbia 

(D.C.) from 2000 to 2014. Increases ranged from 0.7 years for mothers in New Hampshire 

to more than three years for mothers in D.C. (Figure 4). 

● States with larger increases (1.7 years or more) in the mean age at first birth tended to be in 

the western United States (California, Oregon, Washington, Utah, and Colorado). Greater 

increases were also seen in Illinois, Arkansas, and D.C.

● Apart from New Mexico, states with the smallest increases (less than 1.2 years) were all east 

of the Mississippi River, from Tennessee to New Hampshire. 

 

 

 

 

Figure 4. Increase in mean age at first birth, by state: United States, 2000–2014

SOURCE: CDC/NCHS, National Vital Statistics System.

 

 
NCHS Data Brief ■ No. 232 ■ January 2016

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Summary

The average age of first-time mothers increased by 1.4 years from 2000 to 2014, with most of 

the increase occurring from 2009 to 2014. Trends were similar for higher birth orders with fairly 

stable mean ages occurring from 2000 to 2006, and greater increases occurring from 2009 to 

2014. Since 2000, the mean age at first birth increased for all race and Hispanic origin groups, but 

large differences remained among the groups. AIAN mothers had the youngest mean age at first 

birth in 2014 and API mothers had the oldest. 

Since 2000, the average age at first birth has increased in all states, rising 1.9 years or more 

in D.C., California, Oregon, and Utah, while increasing by less than a year in Connecticut, 

Michigan, New Hampshire, and West Virginia.

Continued delays in childbearing in the United States are evident in the 1.4 year increase in the 

average age of first births from 2000 to 2014 (2–5). The decrease in the proportion of first births 

to women under age 20 had the largest impact on this change, while increases in first births 

among mothers aged 30 and over also contributed to the increase in mean age.

Over the past several decades, the United States continued to have a larger number of first births 

to older women along with fewer births to mothers under age 20 (1,5). This trend and the more 

recent uptick in delayed initial childbearing can affect the number of children a typical woman 

will have in her lifetime, family size, and for the overall population change in the United States. 

Definitions

Mean and average age: The arithmetic average of a mother’s age at birth.

First birth: The first child born alive to a mother. 

Race and Hispanic origin: Race and Hispanic origin are reported separately on birth certificates. 

Persons of Hispanic origin may be of any race. Persons of non-Hispanic ancestry are further 

classified by race because there are substantial difference in fertility and maternal characteristics 

between Hispanic and non-Hispanic persons. Persons of AIAN and API ancestry are not classified 

separately by Hispanic origin because the majority of these persons are non-Hispanic. Multiplerace data reported since 2003 were bridged to single race categories for comparability among 

states and for trend analyses (2).

Data source and methods

This report contains data from the birth data set, which is part of the National Vital Statistics 

System (NVSS). NVSS contains all live births reported in the United States. The birth data set is 

the primary data set for analyzing birth trends and patterns in the United States. Birth data sets 

are available from NCHS at: http://www.cdc.gov/nchs/about/major/dvs/Vitalstatsonline.htm and 

http://www.cdc.gov/nchs/VitalStats.htm.
NCHS Data Brief ■ No. 232 ■ January 2016

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About the authors

T.J. Mathews and Brady Hamilton are with the CDC’s National Center for Health Statistics, 

Division of Vital Statistics, Reproductive Statistics Branch.

References

1. Mathews TJ, Hamilton BE. Mean age of mother, 1970–2000. National vital statistics reports; 

vol 51 no 1. Hyattsville, MD: National Center for Health Statistics. 2002.

2. Hamilton BE, Martin JA, Osterman MJK, et al. Births: Final data for 2014. National vital 

statistics reports; vol 64 no 12. Hyattsville, MD: National Center for Health Statistics. 2015. 

3. Ventura SJ, Hamilton BE, Mathews TJ. National and state patterns of teen births in the United 

States, 1940–2013. National vital statistics reports; vol 63 no 4. Hyattsville, MD: National Center 

for Health Statistics. 2014.

4. Mathews TJ, Hamilton BE. First births to older women continue to rise. NCHS data brief, no 

152. Hyattsville, MD: National Center for Health Statistics. 2014. 

5. Gregory E. Ready: Why women are embracing the new later motherhood. Basic Books. 2007.
NCHS Data Brief ■ No. 232 ■ January 2016

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NCHS Data Brief ■ No. 232 ■ January 2016

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Suggested citation

Mathews TJ, Hamilton BE. Mean age 

of mothers is on the rise: United States, 

2000–2014. NCHS data brief, no 232. 

Hyattsville, MD: National Center for Health 

Statistics. 2016.

Copyright information

All materials appearing in this report is in 

the public domain and may be reproduced 

or copied without permission; citation as to 

source, however, is appreciated.

National Center for Health 

Statistics

Charles J. Rothwell, M.S., M.B.A., Director

Nathaniel Schenker, Ph.D., Deputy Director

Jennifer H. Madans, Ph.D., Associate 

Director for Science

Division of Vital Statistics

Delton Atkinson, M.P.H., M.P.H., P.M.P., 

Director

Hanyu Ni, Ph.D., M.P.H., Associate Director 

for Science