Fertility Rate

fertility rate, average number of children born to women during their reproductive years. For the population in a given area to remain stable, an overall total fertility rate of 2.1 is needed, assuming no immigration or emigration occurs.

It is important to distinguish birth rates—which are defined as the number of live births per 1,000 women in the total population—from fertility rates. The single most important factor in population growth is the total fertility rate (TFR). If, on average, women give birth to 2.1 children and these children survive to the age of 15, any given woman will have replaced herself and her partner upon death. A TFR of 2.1 is known as the replacement rate. Generally speaking, when the TFR is greater than 2.1, the population in a given area will increase, and when it is less than 2.1, the population in a given area will eventually decrease, though it may take some time because factors such as age structure, emigration, or immigration must be considered. More specifically, if there are numerous women of childbearing age and a relatively small number of older individuals within a given society, the death rate will be low, so even though the TFR is below the replacement rate, the population may remain stable or even increase slightly. This trend cannot last indefinitely but could persist for decades.

Tracking fertility rates allows for more efficient and beneficial planning and resource allocation within a particular region. If a country experiences unusually high sustained fertility rates, it may need to build additional schools or expand access to affordable child care. This occurred in the United States during the post-World War II baby boom era. During this period, the TFR peaked at about 3.8, roughly twice the average 21st-century rate in the United States. The unusually high number of children born during this period left communities unprepared. Conversely, sustained low fertility rates may signify a rapidly aging population, which may place an undue burden on the economy through increasing health care and social security costs.

Although fertility rates remain well above the replacement rate in many parts of the world, the global TFR has declined significantly since 1970. At that time, the world’s TFR was roughly 4.5, but by 2015 it had dipped to 2.5. In the 21st century, developed countries generally had lower fertility rates than developing countries, as the former tended to have lower childhood mortality rates and greater access to birth control. Higher fertility rates in developing countries reflected the need for children to engage in farming and other economic pursuits as well as the lack of contraceptive access.

Governmental policies related to fertility can take two forms: direct and indirect. Direct policies are those that offer tax breaks or childbearing incentives. The impact of a direct policy on fertility rates is usually immediate. Indirect policies are those that target other societal goals but then inadvertently affect fertility rates. Indirect policies include shifts in child care availability or regulations and laws regarding maternity and paternity leave. Despite the influence that governments can have on TFRs, few policy interventions have worked to reverse low TFRs, although there were some notable exceptions to this rule. France adopted policies that encouraged harmony between individuals’ work and family lives so that young adults would not be dissuaded from bearing children. The French government provided child care subsidies and implemented a reward system for individuals who had at least three children. Sweden followed this pattern by creating more flexible work schedules for women, ensuring quality child care, and allowing more flexible parental leaves.

A country’s social structure may also have an effect on fertility rates. This was especially obvious in Germany after reunification. In East German families, in which the end of the communist system caused economic instability, children were less likely in the years following reunification. In comparison, West Germany’s fertility rate remained relatively stable after reunification. Experts noted that because unified Germany’s political, economic, and social climates mirrored that of the former West Germany, fertility rates in West Germany were uninfluenced by the unification. Similarly, when Poland transitioned to a free-market economy after the fall of the Iron Curtain, it experienced a marked decrease in fertility rates.