The population of the world surged from 2.8 billion in 1955 to 6.5 billion 50 years later because birth rates remained high at the same time that death rates began to fall. The number of children that a couple will have is determined by many factors, including health, religion, culture, economic status, and the ability to have the number they wish to have. Many of these factors relate to the status of women—the social, economic, and cultural circumstances of women in society and of individual women in different societies. Because these factors help determine the number, spacing, and timing of births, women's choices (or lack thereof) regarding childbirth directly affect population growth.
Factors Affecting Family Size
Biological, cultural, and socioeconomic conditions together determine the number of children that a woman will have. These conditions influence her exposure to intercourse and her ability to conceive a child, as well as the number of children she may wish to have. Some factors include age at marriage, use of family planning methods, and breastfeeding. Many socioeconomic factors are also important influences on fertility. These factors are sometimes indirectly related. Education, urbanization, labor force participation, and infant mortality have a strong correlation with levels of fertility. But it is difficult to determine direct causation and one must be careful not to confuse causation with correlation. Some factors may be merely related to fertility rates, and other unknown factors may be the real cause of different levels of fertility among different women and different societies.
Women's Age at First Marriage and Family Size in Selected Countries, 2000s
Source: Demographic and Health Surveys, 2001-2006; Indicators of Marriage and Fertility in the United States from the American Community Survey: 2000 to 2003, US Census Bureau; Carl Haub, 2007 World Population Data Sheet (Washington, DC: Population Reference Bureau, 2007).
Generally, the age at which a woman first marries is directly related to the number of children she will bear because it affects the length of time she will be at risk of becoming pregnant. Of course, unmarried women may also have children, but the vast majority of childbearing takes place within marriage throughout most of the world, which makes the age at marriage a valuable indicator of a woman's lifetime fertility. The total fertility rate—or average births per woman—for women in the United States, who marry around age 25, is 2.1. Conversely, women in Niger, who marry earlier, average 7.1 children (see chart, "Women's Age at First Marriage and Family Size"). Within countries, rural women tend to marry earlier than urban women and tend to have larger families. Access to contraception is an important contributor to the differences in the fertility rates among countries, but culture and socioeconomics weigh heavily as well.
Women's access to education, health care, family planning, and employment all affect family size. Studies show that women who have completed primary school have fewer children than those with no education. Education is key because educated women are more likely to know what social, community, and health services, including family planning, are available and to have the confidence to use them. In addition, women with more education have more opportunities outside the home and can see the benefits of education for their children. Women who achieve a relatively high level of education are also more likely to enter the labor force before they marry or begin childbearing, and ultimately to have smaller families than women who marry in their teens. This trend is evident in almost every country where data are available. As the figure "Women's Education and Family Size" shows, women with a secondary school education have substantially smaller families than women with less education.
Women's Education and Family Size in Selected Countries, 2000s
Source: Demographic and Health Surveys, 2003–2006.
Evidence shows that efforts to lower birth rates may depend on improving the status of women. Part of the Cairo Programme of Action, developed at the 1994 International Conference on Population and Development, calls for universal access to education, employment opportunities for women, and an end to discrimination against women. Experiences in some countries have shown that fertility patterns can change in as little as a decade, and that voluntary policies and programs can be highly effective in encouraging the change.
Birth rate (or crude birth rate): The annual number of births per 1,000 total population.
Death rate (or crude death rate): The annual number of deaths per 1,000 total population.
Family planning: The conscious effort of couples to regulate the number and spacing of births through artificial and natural methods of contraception.
Infant mortality rate: The annual number of deaths of infants under age 1 per 1,000 live births.
Life expectancy: The average number of years a newborn infant can expect to live under current mortality levels. Most commonly cited as life expectancy at birth.
Literacy: The ability to read and write.
Total fertility rate (TFR): The average number of children a woman would have assuming that current age-specific birth rates remain constant throughout her childbearing years (usually considered to be ages 15 to 49).
An Example From India
Women in the southern Indian state of Kerala demonstrate the role of a woman’s status in lowering birth rates and improving child and maternal health. Kerala is primarily rural and agricultural, as is most of India. The residents have low incomes. Yet, in the early 1990s, women in Kerala were bearing about two children, on average. That is the same as the average in the United States today, and less than the average for India (2.9). Between 1970 and 1992, Kerala’s TFR dropped from 4.1 to 2.0 children per woman, the largest decline of any Indian state. By the mid 2000s, the total fertility rate was down to about 1.7 children per woman. The infant mortality rate is also low, 12 infant deaths per 1,000 live births.
Why are the women in Kerala different? One obvious difference is their higher educational level. While many Indian women cannot read and write, 88 percent of women in Kerala are literate. The state government has assigned a high priority to ensuring that all residents have access to education.
But today’s high literacy rates and good maternal health are only two indicators of the higher status women in Kerala have enjoyed for a long time. In traditional Keralese culture, women can inherit land and wield some political power—a sharp contrast with other parts of India. And, while in most of India girls are considered a drain on family finances because their parents must pay a dowry to marry them off, Keralese women bring their families a brideprice. In Kerala, girls are considered an asset.
Demographic and Socioeconomic Indicators in India and the United States, 2000s
|Total fertility rate
|Infant mortality rate
|Life expectancy (male)
|Life expectancy (female)
|Contraceptive prevalence (all methods)
Sources: Carl Haub, 2007 World Population Data Sheet (Washington, DC: PRB, 2007); Sample Registration System, Registrar General of India; and National Family Health Survey 2005–2006 (NFHS-3).