The saying “demography is destiny” reportedly dates back to 19th-century social scientist Auguste Comte, and it’s still popular among journalists. Earlier this year, for instance, Alan Wheatley of Reuters warned about the challenges Asian countries (especially Japan) will face as over-60 residents make up ever-larger shares of their populations. His article also touches on the challenges for countries that face the opposite problem: a large proportion of young residents, or “large cohorts of angry, unemployed young men” prone to causing turmoil.

A recent Council on Foreign Relations report, Family Planning and U.S. Foreign Policy, describes the relationship between rapid population growth and civil unrest and recommends that US foreign policy and assistance focus more specifically on fertility rates. Authors Isobel Coleman and Gayle Tzemach Lemmon explain the issue this way (references omitted):

The connection between demography and political instability is not linear, and there is certainly no demographic threshold that when met “dooms a state to upheaval or tyranny.” However, rapidly growing populations are more prone to outbreaks of civil conflict and undemocratic governance.

The age structure of a country is a particularly useful indicator for analyzing the risk of conflict in a certain country. A population age structure refers to the relative proportion of different age groups within a country’s total population and reflects a country’s progression through the demographic transition. Countries characterized by a very young or youthful age structure–where at least 60 percent of the total population is under the age of thirty–are more likely to experience civil conflict or undemocratic governance than those with a more balanced age structure.

They note that these demographic factors are intertwined with the global trend toward urbanization:

Urban growth and the youth bulge are connected. In countries where agriculture is declining, many young adults migrate to urban centers in search of education, employment, and opportunities for immigration. Urban centers, which are fertile grounds for the expression of political protest, tend to have unusually high proportions of young adults in their working-age populations. This same research has shown that growing trends of urbanization, along with a growing youth bulge in many countries, are exacerbated by low levels of per capita cropland and/or fresh water. Taken independently, these two factors are not seen to be a risk factor in civil conflict, but paired with the known risks of urbanization and a youthful population, they can become destabilizing. In the 1990s, approximately half of all countries with high proportions of young adults and low levels of one or both of the critical resources of crops and fresh water experienced an outbreak of civil conflict.

Other researchers have argued that scarcities of critical natural resources undermine the ability of agricultural economies to absorb the available labor pool, which promotes landless poverty and accelerates the growth of urban slums. When jobs are scarce, a large and growing youth bulge can lead to increased discontent, crime, political unrest, and radicalism. High rates of urbanization can also produce slum housing and inadequate services, increasing the risk of crime and civil unrest.

Slower population growth can reduce these pressures, and over the past few decades several countries have succeeded in reducing fertility rates by expanding access to family-planning services. Coleman and Lemmon report that fewer than 10% of women of reproductive age in the developing world were using modern family planning in 1965; by 2005, that number jumped to 53% (and this excludes China). As a result, the average number of children born per woman has dropped from more than six to slightly more than three.

Family planning isn’t just about ensuring that fewer babies are born; it’s about allowing women to time and space their children’s births to improve health and survival prospects for mothers and babies alike. Girls who give birth when they’re between the ages of 15 and 20 face double the risk of death of women in their twenties – and nearly 1,000 women are dying each day from pregnancy-related causes, Coleman and Lemmon remind us. And the spacing of pregnancies is also important:

Pregnancies occurring less than six months after a preceding live birth are associated with a 150-percent increased risk of maternal death. The risk of newborn mortality is also very high for children conceived six months after the birth of the preceding child–this risk is three times that for a child born at least thirty-six months after the preceding birth.

High-quality family planning has been demonstrated to reduce maternal, infant, and child mortality – and these positive outcomes can lead to other benefits:

High fertility rates can lead to a vicious cycle of poverty at the community, regional, and national levels. The quality and availability of family planning services is instrumental in interrupting this cycle and creating stronger, more stable families and communities. Increased access to modern family planning allows men and women to lead healthier lives and has a positive domino effect on their socioeconomic environment, including a decrease in the high costs of social services (such as health services, education, and social safety nets), a decline in the burden of unemployment, and reductions in stresses on infrastructure needs (such as water, sanitation, energy, transportation, and housing).

In addition, research has shown that slowing population growth is an effective strategy for reducing greenhouse gas emissions. One recent paper states: “Using an energy-economic growth model that accounts for a range of demographic dynamics, we show that slowing population growth could provide 16 to 29 percent of the emissions reductions suggested to be necessary by 2050 to avoid dangerous climate change.”

The authors cite research that calculates fulfilling today’s unmet family-planning needs would cost $3.6 billion more than what’s already being spent – but that investment would save $1.5 billion.

“In 2007 alone, U.S. international family planning assistance enabled modern contraceptive use by more than 56 million women in the developing world,” Coleman and Lemmon write. Still, we could do more. The report closes with five recommendations for the US:

1. Prioritize family planning in U.S. foreign policy
2. Increase U.S. family planning funding
3. Increase access to family planning
4. Encourage political support for women’s health within countries receiving aid
5. Expand resources into countries with highest unmet need

As Coleman notes in a blog post at The New Security Beat, international family planning is a controversial issue in US politics. If we reduce or withhold family-planning assistance based on economic or political concerns, though, we’ll be missing out on a cost-effective way to promote a healthier, safer, and more prosperous world.