The world our three granddaughters will inherit will be different from the world that we have known. I hope that their world in half a century is not too ghastly—and there is reason to support that hope.
The risk of extreme overpopulation seems to be waning. The global TFR (the number of children a woman will bear) is close to replacement. Also, the number of global unplanned births approximates the net number of people added to the planet each year.
In 2020 the global TFR was 2.3. In 1990, just 30 years ago, the TFR was almost one child larger, at 3.2.
The global TFR was over 5 when I was born in 1943 and has been dropping ever since. For a country with a low child mortality rate, replacement TFR is about 2.1. That is one child to replace the mother, another to replace the father and one tenth to account for children who don’t live to reproductive age. That number is higher where the child mortality rate is high—2.2 or 2.3. Fortunately, child mortality has dropped considerably in the past 3 decades, which is why we use 2.1 for the goal of ZPG (Zero Population Growth). We have made amazing progress!
Well, if the TFR is so close to ZPG, we don’t need to worry about overpopulation, right? WRONG! There are three problems with that contention. Most important is that the planet is already overpopulated. We have almost 8 billion people on Earth, whereas 3 billion would be sustainable. To get our population down to a sustainable number without massive mortality will require a TFR close to 1. Second, it has taken many years to lower the TFR to 2.3, and most of the “low-hanging fruit” has been picked. It will be difficult to get it to 2.1 or below. Third, population momentum will keep growth going for decades after we reach ZPG since there will be many young people who will be starting their families. We will need a TFR significantly less than 2 in order to reach a sustainable population. Today’s children, including our granddaughters, will be happier and safer if the world becomes less crowded rather than more so.
The number of unintended (or unplanned) pregnancies globally is about 120 million each year. What is an “unintended pregnancy”? Social scientists recognize that there is a spectrum of desire. At one end of the spectrum are our two sons who were definitely planned—and also very much loved. At the other end of the continuum might be a pregnancy that results from rape during war.
The global rate of unintended pregnancy has dropped from 79 to 64 per thousand reproductive-aged women from the early 1990s to the late 2010s. The global abortion rate also dropped slightly in the same 25-year period. Safe, effective contraception has helped lower both of these rates. Of those 120 million unintended pregnancies, many will be miscarried and others will be aborted, so perhaps 80 million are carried to term.
It is coincidental that the number of unintended births is close to the net growth of our population. If we can make family planning services available to all people, there is a good chance that global population will stabilize or start to decrease. Because we consume the most, we in richer countries must have the fewest unintended pregnancies. Remember, consumption multiplied by the number of people determines environmental impact. Therefore, unintended pregnancies cause the most impact in rich countries, such as the USA. In this same 25-year period, the unintended pregnancy rate has dropped by almost half in Europe and northern America, some of the world’s richest countries.
Unfortunately, there is also bad news. Politicians are not very interested in investing in family planning, although it has been shown that every dollar spent would save many dollars for maternal and newborn care—and save many lives of women and children.
© Richard Grossman MD, 2021