Because human eggs can’t be frozen and still be viable. Sperm can and so can fertilized embryos, but not eggs.
Incorrect. Human eggs can be frozen and successfully thawed and used - it’s just not nearly as successful as either freezing sperm or freezing embryos. Only a third or less of such eggs will survive the process, but since women have quite a few eggs if you freeze a few dozen it should be plenty for any one women’s reproductive needs. Or even the needs of several women as long as your last name isn’t “Duggar”
Was unaware of that. I’d heard somewhere that eggs could not be frozen and remain viable.
At any rate, it looks like the limiting factor, at least initially, is going to be number of trained personnel. I thought it was going to be amount of sperm. So even if they develop the process of two women making a baby, as was suggested earlier in the thread, the lack of trained fertility workers will still be the main issue. That’s something I hadn’t considered.
I think that amount of increase in doctors and lab techs is not unreasonable given that it’s an increase in a particular quite small sector of the economy, not an increase in the total number of doctors and lab techs. I imagine, for instance, that retraining obstetricians to be fertility doctors would be a hell of a lot easier than creating new fertility doctors from scratch … and there are going to be a whole lot of obstetricians in need of retraining for * something*
You’re probably right about retraining existing medical professionals being easier, but we’d also have to retrain all the existing fertility docs to whatever the new process is going to be (once it’s been invented). If you’re a lab tech that knew how to take sperm + egg and make a fertilized embryo before, but this new process doesn’t use any sperm, your existing skillset may be of limited value. And every year we wait while developing the new process and getting it up and running is leaving a giant hole in the world’s population, kind of like a reverse baby boom. Imagine if we’ve got a 15-year gap wherein essentially no babies were born. 18 years later we’ve got no one going to college or entering the workforce, because essentially no people were created between 2021 and 2036. Imagine how disruptive that would be to the economy, to civilization itself: Diaper manufacturers would be out of business by 2036. Cartoon makers, elementary school teachers, colleges, etc, all had a 15-year rough patch of no customers. Imagine all the institutional knowledge that would be lost in that period. Companies would have to fight to lure away employees from other industries / competitors like starving dogs fighting over scraps, because the labor supply is drying up. Militaries and police forces (and every other physically-demanding job) would be manned by middle-aged men by the time the first test-tube-born youth were ready old enough to replace them.
We sometimes talk about the conflict / friction / differing perspectives that exist between Baby Boomers and Millenials, for example. That sort of inter-generational conflict would seem tame when we get to 2050 and we’ve got a crop of teenagers whose next-oldest role model is in their 30’s. They grew up their whole lives without older brothers / sisters / cousins, neighborhood kids to look up to and learn from.
BTW, OP, this is an interesting hypothetical (at least to me), but the more I mull it over the more I think “civilization” would be largely screwed, even if we didn’t nuke each other into oblivion while fighting over frozen sperm.
Okay given the conditions and parameters set by the OP, I’ll say 80 years.
Did I win?
If our alien space bat nemesis remains present, we’ll see a gradual but steady ageing in all populations as mortality without replacement will outweigh any success with frozen embryos. Total global population will fall steadily.
Some broad economic implications:
As with lots of things this will be less totally bad if you are white, western and rich. I suspect IVF and other related technologies are very unevenly spread across the planet. Obviously in a decade we won’t have to worry about wasting money on pre-school or kids toys in much of the world, but many economies remain reliant on under-age labour.
Also old unproductive people get taken care of by the attention and taxes of the rest. In my part of the world there is already concern that the ageing baby boomer generation is imposing increased elder care and health costs on the rest, so this uneven taxpayer-welfare model will continue to skew and only get worse.
We invest money on the logic that it will retain its value and then some in the future. We build infrastructure with a 100+ year design life. Will that even be relevant when the global population will dwindle to a fraction of itself. Why bother saving or planning for tomorrow?
Given how much will be invested in each new IVF human, will we be able to sustain a large enough proportion of them to produce food for the rest? Or to maintain the knowledge we need to keep the hi-tech society that may be able to deal with this running? Will it be a good use of the diminishing supply of youngsters to care for the growing sea of old folk? It may be more effective to kill everyone when they turn 50, because they will be a nett drain on whatever system eventuates.
I always thought Logan’s Run was crap logic, but I can see pockets of cocooned geriatric privilege and an ocean of uncertain quality of life after Space Bats arrived.
It would seem counterproductive to start killing people, even old broken ones, when we’re in the middle of a shortage of people.
Since any answer to the OP requires a lot of speculation, let’s move this to IMHO.
Colibri
General Questions Moderator
You didn’t think sterility-causing space bats was strictly factual? 
We can maintain civilization with a lot fewer than half a billion people given that we’d have plenty of time to retrench. First, automate like hell. No more arguments from Tucker Carlson. 
Second, as already covered, get IVF really going.
If this is a story, you might wonder who gets the benefit of IVF. I’m betting poor countries will crash a lot more than rich countries, unless the aliens implanted some empathy. Fewer people means fewer farmers are needed. We’d spread out after land becomes unoccupied as people age and die faster than IVF can replace them. But maintaining an infrastructure for working at home doesn’t take that many people.
That’s long term. Short term there is going to be a problem when there is more old people than young people to take care of them. But that isn’t civilization ending.
When we run out of sperm, we might wind up with women only. But that won’t destroy civilization either.
One group who’d probably do surprisingly well at least initially would be poor children in the developing world. It would suddenly be in the interests of their own governments to start spending resources on keeping them alive, well fed and productive in a way that it wasn’t when there were plenty more where they came from. Assuming that fertility techniques would be developed that ultimately were able to provide replacement-populations, but at a greatly reduced population size to what we have today, the birth rate in the developing world would go down a lot more than in the rich West, but not to absolutely nothing, since there are still wealthy elites who can afford expensive medical procedures pretty much everywhere. Developing countries would be trying to get their own fertility facilities as a matter of priority, and would probably clamp down on medically trained people leaving the country for higher paying jobs in, eg, the NHS. Simultaneously, people with newborns would jump to the front of immigration queues all over the West … in fact, we might even see a reversal of the current pattern of rich countries desperately trying to keep poor refugees out, though anyone over 30 without kids would still be SOL
You seriously think everybody quits being productive by 50?
Average age of farmers in the USA is currently 58. Even with modern equipment, it’s a fairly physical job.
Fair enough - i picked an age more or less at random, and the notion of sacrificing the elderly itself to be provocative. Does it work better if we pick 60? 70?
Geronticide(?) is not necessarily what I’d be voting for in the informed plebiscite which governments would use decide how we deal with this existential crisis, independent of our personal interests (a fantasy that makes Alien Space Bats seem even more real by comparison).
That was the premise of Michel Houellebecq’s The Elementary Particles, although this only becomes apparent at the very end of the book.
Coincidentally, I read it exactly 20 years ago.
If children born from IVF and implanted embryos also become sterile due to the space bats, we have maybe fifty years or so to come up with human parthenogenesis. And it is going to have to scale up PDQ to replace the current method.
“The human brain is the only computer that can be made with unskilled labor.” We would have to make the conclusion of The Iron Dream into a documentary.
Regards,
Shodan
Do people even know this is happening? I mean, it’s not like if people’s legs (or third leg) are falling off, and most people aren’t trying to impregnate anybody most of the time. An increase in failures to impregnate is going to take a relatively long time to be noticed - possibly months or even years could occur before a full-blown societal panic set in, if people weren’t made aware of the disease’s effect by other methods.
I don’t believe that existing sperm supplies could possibly make any significant difference, so the question in my mind comes down to how well society would fare if people suddenly stopped having babies. Coupled with what would happen when people found out there would be no more babies.
The latter could be bad. I could see society as a whole becoming despondent, angry, or panicked. Religious groups screaming about the end of times, leading to rioting, general destruction. If you wanted to your story could functionally have society coming to an end days after the alien space bats tell everyone what they did.
If this doesn’t happen, you’re probably going to see things carry on for a while, with people carrying on with their daily lives largely unaltered, give or take things like elementary school teacher being a less appealing college major. Society could carry on for several decades, but gradually everyone is going to age out, and society will collapse due to lack of things like power/sewage plant maintenance and food production/distribution. This’d probably happen when the current babies are around fifty or sixty (as a total guess); at that point I figure there won’t be enough fit, trained, and motivated people left to keep everything necessary going in most regions.
Or, alternatively, you could have presumed that society would have stepped up its automation in the face of future decline, and that over the next fifty years reasonably aware robots had been created to take over all the jobs nobody was inclined or able to do anymore. Due to the nature of the extinction these robots would have to be continually stepping in and replacing departing workers, so after a certain point all the humans would be gone and society would continue on with robots alone.
Years? I don’t think it would even make it a week.
The relatively small fraction of people who are actively trying to get pregnant might not notice for a while if they don’t get pregnant for a few months because it often takes a few months or longer to get pregnant even when trying, but every OB/GYN in the country is going to notice when they just stop getting new patients. After a few days they’ll be calling their colleagues in disbelief and a few hours later it’ll be the biggest international news story of tall time.
This is not the sort of thing that could go unnoticed.
I suspect that if all of a sudden nobody was getting pregnant, we would notice within six months, tops. Probably more like three.
Dr. Babycatcher is going to sit up and take notice when he hasn’t received a single new patient for two weeks. Then he starts asking around, and finds the same for every OB-GYN in town, and the country, and the world.
Regards,
Shodan
In the story, at first it’ll just be a boom time for pregnancy clinics as lots more than the usual number of infertile couples seek help. Eventually someone is going to note the extreme number of sterile males (when not only the males from the couples, but also their sperm donors come up blank) and sound an alarm.[sup]1[/sup] No doubt there’ll be studies that verify it and then a search for any non-sterile males. Perhaps they’ll even find a few who haven’t gone completely sterile yet (haven’t decided on that, yet). No doubt there’ll be panic and such when the word gets out. The story I’m actually thinking about will happen some years after. As I said, this is background for the story.
ETA: it’s not going to be sudden in the story. It’s going to be a gradual thing. Forget the Alien Space Bats, they aren’t actually part of the story.
[sup]1[/sup] There already has been an alarm for greatly reduced fertility among men, at least in most of the developed world. It was first noted back in the 90s. So far, no panic among the general populace.