With the world confronting a host of major crises relating to climate, energy, severe poverty, food, the global economy and political instability, why should anyone be concerned about population? The simple answer is that improving access to family services and information, while also addressing the gender inequality that contributes to high fertility, can make a world of difference. A critical difference.

Reproductive freedom—the ability and capacity of people to decide for themselves whether and when to have children—is a basic human right, one that is crucial to personal fulfillment and wellbeing. But it is not just a human imperative. It is also a global imperative.

While public concern about rapid population growth has subsided in recent decades, world population is still growing at about 80 million people a year, or about 220,000 people per day. If current trends persist, there will be at least 2 billion more people on the planet by mid-century, bringing the total to nearly 10 billion. That projected population growth presents a host of challenges, especially for the least developed nations.

Over the past two decades, the world has made significant strides in reducing global hunger and severe poverty, but progress has been elusive in areas where fertility rates remain at or near their historical highs. In many parts of sub-Saharan Africa and in parts of South Asia, the number of people who are chronically malnourished or severely impoverished is still on the rise. Unless more is done in these areas to educate girls, eliminate child marriage, empower women, and improve access to family planning, fertility will remain high and little or no progress will be made in improving the health and wellbeing of women and their families.

In areas where land, water, and other resources are in short supply and population density is already high, population growth contributes to resource scarcity and environmental degradation. Unless more is done to reduce the barriers to family planning, including child marriage practices and other harmful gender norms, efforts aimed at halting deforestation, loss of topsoil, and depletion of water supplies are likely to fail.

In the United States and other advanced nations, where our carbon and ecological footprints are exceptionally large, doing more to prevent unintended pregnancies can make a contribution to mitigating our carbon footprints and making the world more sustainable.

Doing more to prevent unplanned pregnancies will not, by itself, save the world. We must do far more to restrict greenhouse gas emissions and reduce the overconsumption of land, water and other resources that imperils our future. But population is too important to ignore. Improving access to family planning is important for the health and success of families, but it can also make a highly cost-effective contribution to solving many of our global challenges.