Fertility Fears Overblown: Tiny Shift in Childless Rate Saves The Species

All know that women, and the men who mate with them, are having fewer babies. There is substantial variability depending on locale, but the trend pretty much everywhere around the globe is down, down, then down some more.

Some worry the trend will continue and that, in due course of time, man will go extinct. After all, if the ladies are pursuing everything besides babies, there is not much hope for the future.

Naturally, there are causes of this, as there are of all things. Indeed, there are as many causes as there are women and men—and days, since decisions to have a child or not are not always final. This is what makes it so easy to bicker about what is causing baby-free choices.

My own theories are (1) Equality, and (2) ICU. These two together, I say, are the leading causes for lack of kids. Equality drives women to “careers”, where they wait too late to have babies. I have said enough about Equality in other places that I’m sure you take my meaning.

ICU is “I see you”, a.k.a. the There Are Too Many People Around theory. People look around, see lots and lots of people everywhere they go, and say to themselves, “Why bother having more?” Especially as people are more disconnected, shoveled into hovels inside teeming cities, and not tied to place, a phenomenon itself caused or exacerbated by Equality; it’s difficult to desire to put down roots.

Two economists come close to these theories with their insistence Modernity itself is the culprit of the baby bust.

The paper is “Terra Incognita: The Economics of a Shrinking World” by Fernandez-Villaverde and Norrick. They say “modernity itself, which makes a third child expensive and childlessness cheap” is causing the continuing drop in Total Fertility Rate (TFR).

Regardless whether this is right, they also note the global fall in TFRs. “Will they recover?” they ask. Maybe not, they say, but they won’t swear to it: “We are entering demographic terra incognita“. This could be the end. We could already be extinct and not know it!

Since part of Modernity is, of course, Equality, though this is often unacknowledged, I cannot help but agree with them, up to a point. The pair are focused, as would be expected of economists, on the money aspects of birthing babies. These are not unimportant considerations, but they are not, I think, as compelling as they argue in their model.

They say things like children are a “luxury good”, which is a poor choice of words. People envy luxury goods, but can’t often afford them. Children do cost money, but more so for the rich, and often because of the many rituals associated with childbirth these days, like over-insistence on Cesareans and excessive pampering. The poor, in contrast, end up not paying much or at all. Luxury goods are also high status. If kids were high status, the rich would envy the poor their children, which they do not.

If you want to see a healthy attractive woman in her prime baby-bearing years with lots of money chasing luxury, and not babies, then this video is probably the single best one you will ever see (trigger warning: it is very depressing):

NYC is so peak ? pic.twitter.com/yfbpb8BBsZ

— Cultured Chud (@cultured_chud) August 19, 2026

But let that pass. What intrigued me about the paper above was the authors’ aptly named section “The unpleasant integer arithmetic of replacement fertility”, which opens with this nifty example:

Imagine a cohort of 100 women. Fifteen end up with no children, a share in line with the completed fertility of recent cohorts in Europe and the U.S. (Sobotka, 2017). Of those 15, around 5 are childless by choice, for professional, affective, or religious reasons; another 5 never find a partner or postpone childbirth until it is too late; and the remaining 5 want children but cannot have them for medical reasons, theirs or their partner’s.13 Of the remaining 85, 10 have one child, 60 have two, 10 have three, and 5 have four. We stop at four to keep the example simple; very few women in younger cohorts have five or more children, and the arithmetic could be adapted to include them.

The 100 women in this population have 180 children, for a CFR of 1.8, roughly the rate in many advanced economies until the early 1990s and in the U.S. until around 2008. And yet we are 30 children short of replacement.

This kind of thing has legs, so I decided to do my own version, which, in the end, shows things are not nearly as hopeless as some say.

The Hopeful Integer Arithmetic of TFR

Let’s start with the observed frequency of women and number of births, taking from “Number of Children Ever Born to Women Aged 40-44, 1980-2022” (here and here). This is for the USA. Officials stop counting at 44 because, though it’s possible to squeeze out a wee bairn after that age, you may as well hope for Harvard to give up DIEing. A not insignificant problem is that some women hear of such miracles and say “That can be me!” No, darlin’, it can’t. Anyway, here is that picture:

The TFR is an “expected value” calculation. Multiply the fraction by the number, and then sum across number of babies. For this data, we get TFR = 1.95. That’s the “expected” (like an average) number of babies per woman. Which is, as you have heard, below 2.1, a number generally considered to be replacement level.

Times past, some women would have more than 9 babies. It still happens now, but rarely. Back then, a lot of kids would die before reaching reproductive age, which inflates numbers of births in the obvious way. Most babies now survive, so modern lower numbers of kids are not as far off in equal effect as in olden days.

Now, as you can see plainly, two babies is the most likely scenario, followed hard by just one or three. With about 18% having none.

It’s that 18% that struck me as curious. I looked up past numbers and it seems the minimum historically is about 5%. It’s never 0% in any large population, because of things like sterility, religion, disease, famine, war, non-procreative sexual practices (Pride, our culture’s favorite) and the like. It will never be the case that all women have at least one baby.

I wondered how low that 18% would have to be before we hit that magic number of 2.1. That means taking from the 18% and giving it to higher numbers of babies. For instance, drop the 18% to 17%, and take that 1% “surplus” and give it proportionately to one and higher numbers of babies, so that each of their rates goes up a bit. Then drop the4 18% to 16% and so on.

But that wouldn’t quite capture what I think would happen. Some of the fraction with just 1 kid would also move higher, and some for two kids would also likely shift a bit higher. So in addition from taking 1% from the 0 kids, I took half a percent from 1 kid, and half from 2, and shifted both proportionately to the right. A small change, really, but I reasoned that if there was a change in attitudes in having more kids, all would shift slightly to higher numbers.

Many other models are possible, obviously. I am not saying this is exactly what would happen, only that it is within the realm of real possibilities. If you have other ideas, please have a go yourself.

Here is the modeled result in TFR by fraction childless:

Somewhere between 12 to 13% childless gets us, at least in the States, to replacement level. That’s a change of only 5 to 6 percentage points. That seems “doable”, does it not?

Evidence in favor of that view is provided here, from the U.S. Census Bureau CPS June Fertility Supplements. This is the observed (well, this too is a Census model/survey) percent childless women by year:

You can see where Equality really hit, and where the borders were opened. Numbers went back up after the covid panic. But they were still in a reasonable range right through the 1980s. By this picture alone, the drop back to childless rates of 12 to 13% do not seem impossible. More on this below.

The other scenario is an increase in Equality and Pride, which would push childlessness even higher. Indeed, I think this is likely in the short-term. I did the same as above, but opposite, taking 1% proportionately from all baby numbers 1 and up and giving it to the childless, then 2% and so on. Probably this is less realistic, because there is a good chance of even fewer higher numbers of births, and a lot more “1”s. Nevertheless, it’s a good first comparison. That gives this picture:

Even up to one-quarter (25%) of all women childless, and we still get a TFR or 1.78 (or perhaps a bit lower, given my warning above). Still, this is not an unrecoverable scenario.

Incidentally, it takes a childless percent of about 58% to get to a TFR of 1. It’s not 50%, because some women would still have more than 2 babies. That’s into South Korea territory, which is also suffering from Equality, but perhaps even more from ICU since more and more people cram into a few large cities. But in that number lies an important clue about how to think about these kinds of statistics.

Limits

It ought to go without saying that only those that reproduce will have offspring who contribute to future babies. That means those who are now devoted to Equality, Pride and the like, the real childless, will not pass their traits on (that can be passed on, and some of that is Cultural). Which means self-destructive—perhaps self-limiting is a better term—traits die out with them. Leaving the future to those couples who have two, three and more kids.

As we’ve seen, even given my admittedly simplistic model, it would not take much to get us back to TFRs of 2.1 or greater. That’s the problem with statistics like TFR: one-number summaries, I mean. They make it seem that all women, and just not some “expected” value of them, are having fewer than two kids, when we see that those having two or more kids outnumber those having one or none (the data, not the model).

Look: the numbers are that 37% of women have one or no kids, while 63% have two or more. Two thirds is twice as bit as one third. And even 31%, about one third, have three or more. It it these men and women who are passing on their traits, and not the childless. All that cheering detail is missed in the one-number TFR.

Equality, Pride, even ICU (including those who work too damn much to maximize money, not families), and the like will burn themselves out. As all things that stand against Reality must. Even if, as I like is likely, they first increase to South Korean levels before.

Video

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