The Family Planning and Environmental Sustainability Assessment (FPESA) project has undertaken an important and challenging agenda, one with tremendous implications for the well-being of human populations and the planet. The project’s finding that there is little scholarship directly linking family planning to environmental sustainability is certainly correct. Having engaged in population-research for over 20 years and been editor-in-chief of the journal Population and Environment since 2007, I believe that the lack of such research is related to key challenges faced by scholars who are potentially interested in the family planning-environment link. These include:

  • Research design challenges, such as: 1) the need to develop long-term studies allowing for potential environmental impacts to be measurable, and 2) identifying comparison groups to contrast environmental change in households and communities that are with and without access to family planning.
  • Complexity and intervening factors that challenge researchers’ ability to isolate the effects of family planning on environmental conditions, since environmental change arises from myriad socio-economic and environmental processes.
  • Demographic theory that historically has not integrated environmental factors; because theory guides academic research, this is one reason that the population-environment connection is under-studied.
  • Disconnects between researchers, practitioners, and funding agencies that constrain collaboration. Practitioners require timely evidence of programmatic impacts, yet academic research can take years to appear in peer-reviewed scientific journals. Funding for basic social science research also is increasingly difficult to obtain and, if received, often requires many rounds of proposal submissions. These challenges mean that the basic research endeavor can sometimes move very slowly.

Even so, creativity can help overcome some of these challenges.

Individual, Household, and Environmental Factors Affecting Food Choices and Access – Supplemental Nutrition Assistance Program – NCBI Bookshelf (

Innovations in research design

Innovative approaches to research design can allow for the exploration of alternative futures under different family planning and population scenarios, without requiring long-term studies. Two examples, from China and the United States, illustrate this approach.

china development

The Wolong Nature Preserve in southwestern China’s Sichuan Province is home to 4,500 people while also providing critical habitat for the endangered giant panda. To simulate future habitat loss under a variety of family planning scenarios, researchers from Michigan State University used “agent-based modeling.” They first linked population and household dynamics to land use and then estimated the amount of habitat change projected under different family planning scenarios.

The researchers found that family planning—and related factors such as fertility rate, birth spacing, and upper reproductive age—have almost immediate impacts on human population size. Although overall fertility changes shape habitat loss only in the longer term (40 years), increasing the maternal age at marriage would produce positive habitat impacts in only 10 years.

In a second example, Oregon State University researchers used mathematical modeling of the contribution of population to climate change by estimating the extra carbon dioxide (CO2) emissions caused by childbearing—an individual’s “carbon legacy” as related to fertility choices. When considering descendants across two generations, under current conditions in the United States, they found that each child adds over 9,000 metric tons of CO2 emissions for an average individual. This suggests that a reduction of one child would bring dramatically more emission savings than reducing driving miles (147 tons saved), replacing single-paned windows (121 tons saved), and replacing lightbulbs (36 tons saved).

Other innovations in research design include embedding “comparative potential” within family planning interventions. For example, based on data from a quasi-experimental design in the rural Philippines, Leona D’Agnes and colleagues determined that programs that integrated reproductive health and environmental conservation yielded greater socio-environmental outcomes than programs that offered either in isolation. By collecting pre- and post-project data in communities with different types of interventions, statistical models could be used to estimate the utility of linking family planning and conservation efforts. The integrated programs yielded greater reductions in the average number of children born.

With regard to challenges posed by complexity and intervening factors, innovations such as those outlined above help to focus analytical attention on the environmental implications of family planning and changes in fertility.

Integrating the environment into demographic theory

In addition, the FPESA project has piloted the intriguing approach of disaggregating the association between fertility and the environment into its constituent parts. On one side of FPESA’s conceptual framework, we find the negative impact of high levels of human population on environmental sustainability—a statement that few would disagree with today. This association is demonstrated in Figure 1 as the correlation between future population and emission projections.

global emissions graph
Differences in Annual Carbon Dioxide Emissions, Based on Low, Medium, and High Projections of World Population Growth, 2000–2100, globally (dashed and center lines) and by region (shaded areas). Illustration from Brian C. O’Neill et al., “Global Demographic Trends and Future Carbon Emissions,” Proceedings of the National Academies of Science of the United States of America, vol. 107, no. 41, p. 17524.

But FPESA’s approach also considers the importance of focusing on research that examines the connection between family planning and population growth. This body of work is vast and includes insights related to women’s unmet need for contraception, factors influencing contraceptive uptake, and impacts of improvements in (or absence of) reproductive health offerings. Documenting what is known about this connection should help activists, practitioners and policymakers better make the connection between family planning, population growth, and, ultimately, environmental sustainability.

5 Methods to Identify Environmental Aspects and Impacts – SolutionsTRAK

Bringing these pieces together by summarizing research reflecting the constituent parts should help inform the demographic theories that guide fertility and other demographic research. Ultimately, the expansion of demographic theories to better integrate environmental concerns will go a long way toward motivating, and improving, scholarship on population and the environment.