• Topic: Advocacy
• Article on Advocacy

KEY POINTS The faster fertility levels fall, the smaller the world's eventual population size.
1	Continued population growth will increase need for services. Population growth alone will mean that 440 million more couples will need family planning 20 years from now, even if the percentage using contraception does not increase.
2	Acting now to support family planning programs helps avoid future population pressures. Programs have contributed to lower fertility levels by helping millions of women to avoid unintended pregnancies. Even small declines in average family size have a large impact on the number of people within a few generations.

According to population projections considered most likely, 1.6 billion couples will be in the reproductive age group in 2020, nearly twice as many as at present (248). Without any change in the percentage of people using contraception, in 2020 there would be some 880 million contraceptive users and 200 million women with an unmet need.

Over the past few decades, as fertility rates have fallen, world population growth has slowed. Population is growing at an annual rate of 1.3%, estimated in 1998, compared with 2.1% in the 1960s. Nevertheless, the world's population is growing by almost 80 million per year—about 1 billion every 13 years (246). Even if fertiltiy rates continue to fall as projected, the number of people will continue growing substantially (see Figure, below).

Even lower fertility rates can mean large numbers of births each year, reflecting demographic momentum—the fact that more women are in their childbearing years as a result of high fertility in the past. Even after fertility has declined to the replacement level of about 2.1 births per woman, the rate at which population neither grows nor shrinks over the long term, population continues to grow for at least a generation.

Today, fertility has fallen to or below replacement level in 61 countries, 13 of them in the developing world. In 123 countries fertility is still above replacement level. In most countries couples still have at least three children. About 1.7 billion people live in 47 countries where fertility averages between three and five children per woman. Another 730 million people live in 44 countries in which the average woman has five children or more (227).

While population growth rates will continue to slow in developing countries, the number of people will continue to rise because more women are of childbearing age.

Family planning programs are a wise investment. Since the 1960s family planning programs have played a key role—perhaps the key role—in slowing population growth. Between 20% and 50% of the fertility decline in developing countries has come as a direct result of family planning programs, studies have estimated (5). Still, a study of 20 countries in 1990 found that 22% of fertility was unwanted (28). This statistic suggests that many women who want to control their own fertility have not been able to.

In developing countries, as contraceptive use has risen from under 10% on average in the 1960s to over 50% today, the total fertility rate (TFR) has fallen by about half—from an average TFR of over six children per woman in the 1960s to about three children today (227). In fact, the relationship between contraceptive prevalence and the fertility level in a country is a close one. In countries where contraceptive prevalence is high, the TFR is low; where contraceptive prevalence is low, the TFR is high (see Figure, below).

Differences in average family size have a large impact within a few generations. For example, consider the impact over four generations if each woman had only two children compared with three or with five. If each woman had two children, as in many developed countries today, and each of her children had two children each, and so did their children, the woman would have only eight great-grandchildren.

If, instead, the woman had three children and so did her children and their children, she would have 27 great-grandchildren. If the 5-child family were to remain the norm, as it is in some African countries today, she would have 125 great-grandchildren.

As such numbers indicate, helping couples now to avoid unintended births can make a huge difference in future population size. Family planning is a choice that everyone should have. Family planning helps millions of people today and also helps to assure a better future.