I’m not interested in the cause for the change (will of some god/sterility causing plague/alien bioengineering/rise of ‘childfree’ people/whatever) its just for some reason human births drop by 90%. What are the immediate/short term/longer term results? Okay, in the extreme long term humans go extinct, that’s given and boring.
This happens evenly, world wide, non-violent, no medical intervention needed to cause it. For some reason women just aren’t getting pregnant and giving birth at what used to be the normal rate. For example, Google says about 3 million babies were born in the US in 2020, so now just 300,000 would be born. India drops from 25 to 2.5 million. Monaco goes from 912 to 91.
Okay, there’s an immediate upshoot into investigation why this is happening.
Obstreticians start being affected almost at once.
Diaper manufacturers ditto.
Child care workers start seeing the impact in, oh, maybe six months?
Orthodontists take the hit in around ten or twelve years?
Will enough less milk be needed that dairy farmers cull herds? As the smaller number of children continues on, it will start to impact the need for all foods.
The labor market will be disrupted overall, without free crops of cheap young labor arriving each year. And the continuing loss of older worker will go on as normal aging/death occurs.
How long will it take for people to realize that this is a new ‘normal’ and adjust their planning for it? For example, I’d bet the demand/value of ordinary houses with three or four or five bedrooms would drop precipitously.
Will there be a sudden increase in child kidnapping by wannabe parents? Would we end up with greatly more severe penalties for crimes against children?
On the brighter side, how soon might we see the world start recovering? Children don’t directly drive cars, of course, but would SUVs and such remain popular if the average household mostly consists of single adults or childless couples? Less new housing to create, maybe marginal farming areas abandonned back to nature, less fuels extracted to create energy, on and on.