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Frances Kissling is the president of the Center for Health, Ethics and Social Policy. Jotham Musinguzi is director general of Uganda’s National Population Council. Peter Singer is the Ira W. DeCamp Professor of Bioethics at Princeton University.

Fifty years ago, Paul Ehrlich’s bestseller “The Population Bomb” predicted that the world’s population would double in less than 35 years — a frightening speed. The book had a major impact but spurred a backlash that made almost any further discussion of population radioactive.

As it turns out, Ehrlich’s predictions were extreme. At today’s growth rate, the next population doubling will take nearly 60 years. That slowdown gives us time to find ethical ways of sustaining ourselves and the opportunity to collaborate with stakeholders with differing perspectives on how to do so.

Still, the taboo on talking about population remains.

This may be because of the controversial solutions to rapid population growth that “The Population Bomb” suggested. Ehrlich, a biologist, argued that if voluntary family planning didn’t reduce population sufficiently to avoid famine and other natural disasters, then coercion and the withdrawal of food aid to some countries would be necessary and justifiable.

He had plenty of supporters, but feminists and progressives rejected such draconian solutions. When China initiated its one-child policy and reports of forced abortions emerged, feminists were in the forefront of efforts to end it. Foreign aid policies that set contraceptive targets in return for aid were condemned as violating human rights and disappeared. Feminists also contributed significantly to the taboo by urging a shift away from policies focused on population control to policies supportive of reproductive health and rights. Both feminists and population stabilization advocates now agree that providing reproductive health services to women is first and foremost a right in itself, as well as the best and most ethical way to slow population growth.

Still, the issue of rapid population increase has not gone away. Instead, it has become regionalized. Several European countries and Japan now have negative or zero natural population growth. But the U.N. Population ­Division estimates that 26 African countries will at least double their present populations by 2050. By 2100, Angola, Burundi, Niger, Somalia, Tanzania and Zambia are expected to have five times as many people as they do today. Nigeria already has an estimated population of 191 million, and women there give birth, on average, to more than five children. By 2050, Nigeria is projected to become the world’s third-most populous country.

Many African family-planning advocates are concerned because society with rapid population growth means many dependent children for each adult. If fertility were reduced, there would be fewer children and more adults able to work. And if this potential workforce were adequately educated and had access to jobs, it could become the engine of economic growth, thus paying a demographic dividend to the society as a whole.

Prospects of African prosperity are also threatened by climate change. In regions that are already hot and arid, higher temperatures will make prolonged outdoor physical labor almost impossible and will also increase evaporation, further reducing already strained water resources.

Yet population remains an unmentionable topic in international policy circles. None of the 17 Goals or 169 targets of the U.N. Sustainable ­Development Agenda dares to suggest that it might be desirable to slow the increase in human population, nor does this issue get much attention in World Bank documents. Researchers say they are discouraged from writing about the links between population and climate change or the survival of marine environments.

That should not be the case. The increasing recognition of reproductive health as a human right means there is less likelihood that poor countries will introduce or be coerced into draconian programs of population control. Today we should be able to safely broach the potential problems of population growth and ethical ways to respond to it.

Melinda Gates has shown one way of doing this, by focusing on making contraceptives more readily available to the 214 million women who do not want to become pregnant over the next two years but do not have effective preventive methods. Equally important is providing women with access to emergency contraception following unprotected sex and making safe abortion available to women who need it. The voters of Ireland have clearly indicated that they believe it is unethical to limit reproductive rights for all because of the religious beliefs held by some, and we agree.

Finally, a central part of every discussion about population must be educating girls and women and ensuring opportunities for their participation in work and political life. Women need more options to take control of their fertility and lead fulfilling and rewarding lives.

We have learned a lot in the 50 years since “The Population Bomb” was published. We should not shy away from discussing what actions are ethically permissible to facilitate a stable level of population growth, nor should we leave this discussion in the hands of the affluent. The conversation about ethics, population and reproduction needs to shift from the perspective of white donor countries to the places and ­people most affected by poverty, climate change and environmental degradation.