Diverse Research Interest But Few Firm Conclusions
The body of research potentially useful to documenting the FPESA hypothesis is reasonably extensive. We are reviewing more than 900 peer-reviewed papers published in the last decade based on titles and abstracts that suggest some connection to the linkage we are examining. Many authors of these papers are women and/or are from or working in developing countries, refuting common perceptions that the family planning-population-sustainability linkage has limited appeal beyond developed countries or represents a male or even patriarchal perspective.
The presumption seems common among many scientist that population growth, in particular, is a significant driver of many types of environmental change. In more than a few cases, researchers assemble data or work with models in attempt to demonstrate and even quantify the role of population growth So far, however, we have identified at most a handful of papers that assessors agree are scientifically rigorous and, individually or when combined with other strong papers, convincingly link family planning to environmental sustainability.
Proving the absence of a relationship is next to impossible. It is nonetheless safe to say that we have identified no scientific literature finding, individually or in combination, that there is no benefit of family planning to environmental sustainability. It is also safe to say that there is no sustained debate and apparently little interest among scientists and researchers in attempting to document or refute pathways from family planning to environmental sustainability. Funding is evidently sparse, and the linkage offers little opportunity for professional advancement.
Variability of Topic Coverage
Mentions of population growth and other demographic factors in the identified scientific literature are hardly routine, but neither is it uncommon. Mentions of family planning, by contrast, are uncommon. Mentions of women’s status, education and empowerment in the context of environmental topics are rarer still.
A peer-reviewed article in the journal Science generated newspaper headlines in early 2016 that reaffirms and expands on earlier research suggesting that humanity is breaking past several key planetary boundaries for a “safe operating space for humanity.”
Evaluation: While the article makes no mention of human population, its conclusions underline the importance of considering the linkage FPESA is examining.
Women’s Representation and Environmental Treaties
One article identified a significant correlation between women’s representation in national parliaments and national ratifications of environmental treaties.
Evaluation: Submitting assessors generally felt the article was strong but established more of a correlation than a causal pathway from family planning through women’s empowerment to environmental sustainability.
Population and Carbon Emission
An analysis of demographic and carbon emission trends projected significant savings of emissions from slower population growth between 2010 and 2050.
Evaluation: One assessor criticized this article for lack of clarity in describing its models and explaining its assumptions. Another assessor considered it a strong piece of evidence for the hypothesis that slower population growth is likely to mean lower future trajectories of carbon emissions.
Population and Biodiversity
Another article found what it identified as a probable causative role population density and growth plays in loss of biological diversity.
Evaluation: The article earned generally high praise from most of the assessors submitting. This was tempered by some criticism (potential bias in selection of geographic areas studied, for example, and lack of consideration of consumption factors) and suggestions for additional steps to strengthening the conclusion of causation.
Contraception and Water Pollution
One of the arguably most innovative articles considered the impacts of contraception on estrogen pollution in U.S. waterways. The authors analyzed data on different estrogens entering the waters via sewer systems from the use of oral and other contraceptives and hormonal replacement therapy, as well as from pregnancy. They concluded that the use of oral contraceptives, despite being based on estrogen, tends over time to reduce rather than increase estrogen pollution. Not only does contraception prevent significant pregnancy-related estrogen releases that result from unintended pregnancies, the authors concluded, but prevention of such pregnancies reduces estrogen pollution by future generations, which will be smaller than otherwise due to current contraceptive use.
Evaluation: One assessor suggested that by failing to quantify the estrogenic effects of natural family planning the authors displayed a bias in favor of artificial contraception. But this and the other assessors rated the article positively, while in some cases also suggesting improvements in its methodology and calling for comparable tests based on data from other countries.