May 6, 2010

The New Demography of American Motherhood

Executive Summary

This report examines the changing demographic characteristics of U.S. mothers by comparing women who gave birth in 2008 with those who gave birth in 1990. It is based on data from the National Center for Health Statistics and the Census Bureau. It also presents results of a nationwide Pew Research Center survey that asked a range of questions about parenthood.

Among the key findings of this report:

Overview

The demography of motherhood in the United States has shifted strikingly in the past two decades. Compared with mothers of newborns in 1990, today’s mothers of newborns are older and better educated. They are less likely to be white and less likely to be married.

In 1990, there were more births to teenagers than to women ages 35 and older. By 2008, that had reversed — 14% of births were to older women and 10% were to teens. Births to women ages 35 and older grew 64% between 1990 and 2008, increasing in all major race and ethnic groups.

Another notable change during this period was the rise in births to unmarried women. In 2008, a record 41% of births in the United States were to unmarried women, up from 28% in 1990. The share of births that are non-marital is highest for black women (72%), followed by Hispanics (53%), whites (29%) and Asians (17%), but the increase over the past two decades has been greatest for whites — the share rose 69%.

Just over half of births (53%) in 2008 were to white women, and a quarter (24%) were to Hispanic women. More than half of the mothers of newborns (54% in 2006) had at least some college education. One-in-four (24% in 2004) was foreign born.

The shift in characteristics of motherhood over the past two decades is linked to a complex mixture of demographic and behavioral changes. This analysis examines and explains these trends using data from the National Center for Health Statistics (NCHS) and the U.S. Census Bureau. A separate section (found in the complete report), based on a Pew Research Center survey, explores the reasons people say they became parents and examines public attitudes about key trends shaping today’s birth patterns.

The recasting of American motherhood takes place against a backdrop of relative stability in the total number of births — 4.3 million in 2008, compared with 4.2 million in 1990. The number had risen each year from 2003 to 2007 before declining by about 66,000; the decrease appears to be linked to the economic downturn.

The nation’s birth rate (births per 1,000 women of childbearing age) has declined 20% from 1990. Rates have declined for all major race and ethnic groups. The birth rate for married women is stable, but it has risen for unmarried women.

Demographic Changes

Population changes are a key factor influencing birth patterns in recent decades. There are fewer women in the prime childbearing years now than in 1990, as the youngest members of the giant Baby Boom generation have aged into their mid-40s. But changes in the race and ethnic makeup of young women — chiefly, the growth of the Hispanic population, which has higher birth rates than other groups — have helped keep birth numbers relatively level.

Another influence on births is the nation’s growing number of immigrants, who tend to have higher birth rates than the native born (although those rates have declined in recent years). The share of births to foreign-born mothers, 15% of U.S. births in 1990, has grown at least 60% through 2004. Births to foreign-born women in 2004 accounted for the majority of Hispanic (61%) and Asian (83%) births.

According to Pew Research Center population projections, 82% of the nation’s population growth through 2050 will be accounted for by immigrants who arrived in the U.S. after 2005 and their descendants, assuming current trends continue. Of the 142 million people added to the population from 2005 to 2050, according to the projections, 50 million will be the children or grandchildren of new immigrants.

Attitudes about Birth Trends

Americans are marrying later in life, or not at all, which has contributed to the growth in births outside marriage. Most Americans say they know at least one woman who had a baby while she was not married, and one man who fathered a child while he was not married, according to a Pew Research Center survey. Americans have softened slightly in their disapproval of unmarried parenthood, but most say it is bad for society.

The survey found that Americans are neutral or approving of two other trends that have an impact on birth patterns. One is the growing number of women ages 40 and older who have babies, a group whose relatively small birth rate has tripled since 1990. The other is the increasing number of women, often those over 30, who undergo fertility treatment in order to have a baby.

When Americans are asked what is the ideal number of children for a family, the most popular answer, according to the survey, is “two” — as it has been since the 1970s. And, indeed, among women with childre
n at the end of their reproductive years — ages 40-44 in 2006 — the largest share (43%) had two. An additional 22% each had one or three children, 8% had four and 4% had five or more.

There are race and ethnic variations in family sizes. Nearly half of Hispanic women ages 40-44 with children (48%) have three or more, compared with 27% of Asian women.

The Pew Research Center survey also asked parents why they decided to have their first child, and for the overwhelming majority, the answer is, “the joy of having children.” However, a half century after the Food and Drug Administration approved the sale of birth control pills, nearly half of parents say “there wasn’t a reason; it just happened.”

Older Mothers

The average age for U.S. mothers who had their first baby in 2008 was 25, a year older than the average first-time mother in 1990. Among all women who had a baby in 2008, the average age is 27, up from 26 in 1990. The prime child-bearing years remain 20-34 — three-quarters of mothers of newborns are in this age range. Birth rates peak among women in their late 20s.

Since 1990, birth rates have risen for all women ages 30 and older. Although in some cases the number of births is small, the rate increases have been sharpest for women in the oldest age groups — 47% for women ages 35-39 and 80% for women ages 40-44, for example.

This delay in age of motherhood is associated with delay in age of marriage and with growing educational attainment. The more education a woman has, the later she tends to marry and have children. Birth rates also have risen for the most educated women, those with at least some college education, while being relatively stable for women with less education. These dual factors have worked together to increase the education levels of mothers of newborns.

Fertility Higher Than in Other Developed Nations

Another measure of birth levels is the total fertility rate, or number of children the average woman is predicted to have, based on current age-specific birth rates. That rate for the United States, 2.10 in 20081, is about what it was in 1990. The number is about or slightly below the “replacement rate” — that is, the level at which enough children are born to replace their parents in the population — and has been for most years since the baby bust of the early 1970s.

Compared with Canada, and most nations in Europe and Asia, the U.S. has a higher total fertility rate. Rates such as 1.4 in Austria, Italy and Japan have produced concern about whether those nations will have enough people of working age in the future to support their elderly populations, and whether their total populations could decline in size.

Why are fertility rates somewhat higher in the United States than in other developed nations? Some researchers contend that fertility rates are low in some other developed countries-Italy and Japan, for example-in part because of lack of support for mothers who also hold paid employment. Those countries also have a lower share of births to unmarried women. The religiosity of the U.S. population also has been suggested as a factor, because it is associated with a desire for larger families.2

Read the full report for more details.

  1. The rate before rounding, according to the Population Reference Bureau, is 2.098. According to preliminary 2008 birth data from the National Center for Health Statistics, the rate is 2.086. The replacement rate is 2.100.
  2. Preston, Samuel H. and Caroline Sten Hartnett. “The Future of American Fertility.” National Bureau of Economic Research. Working Paper 14498. 2008.