As Americans, we are obsessed with numbers, but often oblivious to their implications. We love record setting, whether it's the eight Olympic gold medals won by Michael Phelps last year or the octuplets born last month to Nadya Suleman. We derive great vicarious pleasure from these super-human feats.
Technically, of course, Suleman's achievement only ties the American record, as the first set of American octuplets was born about ten years ago in Texas, but she still became an overnight sensation.
Now, however, as more information comes to light about Suleman and her family, a growing chorus, including the American Society for Reproductive Medicine (ASRM), is saying that it shouldn't have happened. ASRM guidelines provide that the in vitro fertilization of a woman of Suleman's age, 33, should transfer no more than two embryos. That's because multiple birth pregnancies put the mother at a higher risk of premature labor and delivery, and her babies at a substantially increased risk of brain injuries and underdeveloped lungs.
As it turns out, Suleman is already the mother of six young children, also born from in vitro fertilization. Fertility doctors are saying that she should not have been allowed to undergo another in vitro fertilization. With fourteen young children at home, many also wonder how a single woman can possibly give her children the care they need and deserve.
But lost in all the debate about the ethical questions that surround Suleman and her doctors are larger questions about the future of human fertility. Many, if not most, Americans believe that global and U.S. population growth is a thing of the past. The media tend to focus on the potential "?birth dearth' in some countries. But population growth, for much of the world, including the United States, is far from over.
While global fertility rates continue to drop, global population, currently 6.7 billion, is still on track to cross the 9 billion mark in forty years or less, and U.S. population, currently 306 million will likely reach 438 million by 2050.
In a world of unlimited abundance, rapid population growth might be a blessing, but in a world wrestling with human-induced climate change, a major food crisis, severe global poverty, stubbornly high infant mortality, environmental degradation, the extinction of animal species, and the steady depletion of oil and other natural resources, concerns about population growth are legitimate.
Part of the problem is that most of us have a poor understanding of exponential growth and its implications. If population grows at 2 percent a year, that hardly seems cause for concern, but a sustained 2 percent growth rate doubles population every 35 years and quadruples it every 70 years. To take a far more extreme example, if a woman were to follow Suleman's example and have 14 children and each of her descendants were to have 14 children, then by the 10th generation this woman would have 289 billion descendants: 43 times the current world population.
Forty years ago, Paul Ehrlich's book, The Population Bomb, warned that sustained population growth could lead to global famine and calamity. In the decades that followed, declining fertility rates and rising agricultural productivity quashed those fears, but as world population continues its relentless ascent, concerns about possible "limits to growth" are increasingly valid. In recent years, there have been alarming jumps in grain, oil and other commodity prices, reflecting the fact that producers are having a harder and harder time keeping up with the rising global demand. Water shortages and climate change, meanwhile, are starting to limit food production.
The world will soon forget about Nadya Suleman and her octuplets, but for decades to come the world will be wrestling with the implications of today's fertility rates. That's the important, and largely untold, story behind all the recent headlines.
Mr. Walker is executive vice president of The Population Institute, a nonprofit organization working to achieve a world population that can live in harmony with the planet. Mr. Walker can be contacted at