I'm sure you all mean well, it's been an overwhelmingly negative response and hasn't really offered me any helpful advice to deal with the situation.
@soshnomore, I am sorry at how overwhelming your thread must be to read & attempt to process - but there honestly is no 'positive' advice to give you, because the response you want does not exist.
Understandably, you would like to hear advice on how to make him change his mind & accept your wishes. He is not going to! - there is no form of words or magic bullet that can sway someone so entrenched in a ridiculous & damaging belief that it's like debating with a child & who arrogantly dismissed your entirely reasonable wishes by informing you that only HE shall have his last word on it & will never forgive you for exercising your basic human right to our own bodily autonomy. So nobody here can give you that.
What we can give you is the benefit of our own hindsight - much of it here hard-won & offered to others following years of horrible freedom-fighting to escape our own abusive relationships.
Please make no mistake - your marriage is abusive, & you have no chance of persuading your husband to respect your choices.
I am not writing this to be negative about YOU - it is screamingly apparent just from your own descriptions of your husband's attitudes. He believes he is entitled to dictate to you, he wishes you to endure avoidable, excrutiating pain for bizarre superstitious reasons, & if he won't hear the facts from ObsGyn professionals, how is there anything you - who he so clearly disrespects - can say to make him see sense?
If you have a child with him, his behaviour will ramp up so fast you will end up barely recognising your old self. How will you feel when the type of nonsense & sadistic disregard he dishes out to you is inflicted on your daughter? Or when he brainwashes his son with his superstitious beliefs & contrary, needless misogyny? Do you want a son who acts out like his dad? - or perhaps even worse, a son who rebels, or is gay, or who wants to embrace any other religion, or even atheism? How will his daughter manage to escape him before he either ruins her mental health or marries her off to some man who shares his own controlling, domineering beliefs? Or she gravitates toward that type of man of her own accord, because that is how familial abuse perpetrates itself in adulthood?
Again OP - I am so sorry. It feels uncomfortable even contemplating the level of strict control you will end up subjugated to, it must be SO horrible for you to read. You may not be ready yet to take all of this on board, I know I would not have been when I was trapped in my own marriage to a coercive controller. But forewarned is forearmed. My ex was so abusive I had to manage 5 months of death threats before the culmination of my divorce - but even HE would not have loftily informed my that now was my time to suffer unnecessary birthing pain, & that if I didn't do it his way, he would never forgive me.
The most concerning aspect is that you do not yet seem to have reached a place where you can take time to properly assess WHY you are still accepting that he has ANY RIGHT AT ALL to tell you what you are going to do with your own body.
Am I being unreasonable to think that ultimately the way I give birth is my decision, and he should have more consideration for how I will feel in this whole thing?
YANBU!
I hope I can explain this properly ... what kind of a number has been done on your poor mind that you even have to ASK this question?
I really, really hope that you will, if not today, be able to process enough that you can come to see that although these are all very harsh words to read, that harshness is NOT directed at you. Quite the reverse. Everybody here is looking to protect you from a life that will not be so easy to escape, should you yield control to this man by creating a child with him.
Again, I sincerely apologise for my own words, which must surely be painful to read. But I don't apologise for the sentiment underlying them, which is utter horror for your situation, & a sincere hope that you can value yourself enough to decide that nobody is allowed to dictate his views to you, let alone impose his bizarre sadistic notions about birth practices on you.
I hope that one day you have exactly the birth or births YOU wish for OP. Just ... not with this guy. 