In all the cases I have seen of it then it is pretty flawed but as you asked there are a few, in addition to things that Foxi4 might be pondering.
"we need more people to fuel our factories/retirement bills and abortion denies us a chance at having them/having them sooner".
The factories bit was actively tried in a few communist states, many still have lingering effects for both sexes (again see the regs regarding getting a vasectomy in Russia -- you have to be quite old or have had several already, compared to elsewhere where you might have to have a look around to find a willing medic but could legally get it done at 18, possibly even on insurance, and plenty have them done in their 20s and consider it a sound financial investment --
https://nypost.com/2017/05/27/hampt...-vasectomies-so-golddiggers-cant-trap-them/4/ ). It did not have a great effect as a net result (unwanted pregnancies tend to make for unwanted children raised in sub optimal environments...).
The latter one I have seen more recently as people look at birth rates being rather below replacement and have banked on there always being more people (more natives being more better for a lot of things, and immigration only works for so long before you exhaust the supplies of quality people and start getting less return on investment, to say nothing of other effects). Why someone else's shit tier financial planning, possibly put in place before I was even born, and unwillingness to react to market conditions (communists, advocate of modern monetary theory, Keynesian, Chicago, Austrian, classical... whatever your position in economics as a whole is then all agree that paying attention to the market, supply & demand, and reacting accordingly is a good plan), means I am supposed to raise a crotch goblin I don't know, not to mention it is debatable that it would even produce more instruments of wealth creation/extraction, but it is still an argument.
Abortion might mostly kick the can down the road but that also means grandparents are then less available (30+30+5 to 7 looking after them= bloody old and decrepit compared to 24+24 + the same, not to mention if we are all supposed to be retiring at 70 or whatever then there is also that) and thus the burden of care shifts either onto the parents, or more likely the state (is the condition of state education a particularly nurturing one that produces well rounded individuals ready to face life, or something that pulls that off coming in cheap?). One also ponders having a career break at 30 when you are probably nicely trained up and bringing in the big money for companies, and having to come back in 5 or so years or only going part time, or not having a break and instead starting reasonably fresh at that time in your mid-late 20s and being to be a good little worker drone (you have 2.3 extra mouths to feed after all). Said drone might possibly be better able to afford a fancy retirement (female poverty rates in retirement is fairly well studied, break to have kids tending to be a big predictor of it) or have your kids get settled in their lives before you get dementia and shuffled into a care home they get to pay for or otherwise geographically restrict them.
I don't know that I have heard it yet but the elements are all out there. Childlessness in women often has some unpleasant psychological effects (fairly well studied, and if nothing else one does not pay the silly money sums for invitro fertilisation and take the massive risks of later life pregnancy (or kick more money to a surrogate), or go through the utter arse ache that is adoption, without a serious underlying drive, one that we can witness in many other animals). Functionally then firing up the womb vacuum might deny them the opportunity to have a kid and in some ways be functionally akin to chopping off an arm because of a condition that says that limb is bad, wind in the issue of biological fertility clocks and issues of older women finding a man ("where are all the good men gone", marriage rates and characteristics thereof, the fun and games of 30 and 40 something divorcees and them finding a new partner...) to that one and it gets even more fun.
There are various places that are more willing to do trade if it is off the table. Most of those having nothing to trade but we are collecting reasons, and who knows what they will dig up tomorrow. On the other hand if one of those is your neighbour and they are doing a roaring trade in taking care of your women as they do a nice day trip just across the border to the womb vacuum and cheap booze shop then it comes back into play.
That would then appear to be several things covering sociological, societal financial, personal financial, international trade, psychological, medical, developmental and similar such reasons, none featuring "because some charlatan in a dress told me in a magic book, written after the fact within a time where industrial farming was not a thing and translated dozens of times since, which I never read yet believe contains truths that it was wrong". How many would stand up in face of no duty to carry a parasite, health reasons, financial reasons, lack sentience in the parasite and all the rest is a different matter, though if we are going to play in societies that are less about the individual and more about the society as a whole (and I don't know that there has ever been a true libertarian state, certainly no big ones) then restrictions and compromises do creep in. Equally is does not have to be restrictions -- too much stick and not enough carrot is a bad plan when you want people do do things.
I imagine it will get even more fun in the future too (the effects widespread of the pill are still being studied after all) when some kind of hypno learning, artificial wombs (already viable for complex mammals and being funded), genetic engineering (see CRISPR), life extension (while above my maths on decrepit ages was more offhand and aimed at being amusing I do note that 50-60 today is not what I saw 30 years ago in the same age range and that is without anything radical happening) and a male pill contraceptive (already in human trials) but I guess we might never see that if whatever the result of this election there will be a hot civil war in the US that kills us all.