How would you feel when you buy a house if I would come in and tell you how to decorate it, where to put the furniture, and what color to paint the walls?
Would you like that? What if I told you my religious sect has very strictly held religious beliefs as to how you can decorate and arrange the inside of your house?
Would you allow my religious sect to control what you do with your house? Why not?
You'd probably insist that what you do inside your house is your business, and that I don't have any right to impose my strictly held religious beliefs on you, because you don't follow my religion, and don't see why my religious beliefs should apply to you.
What's that? You don't want me telling you what you can and can't do with your house? You don't want me imposing my religious beliefs on you? You don't want me sticking my nose where it doesn't belong?
So why do you insist on doing it to others?
Picture your house instead as your body. Would you want me telling you what you can do and can't do with your body and what is inside it? Would you want me telling you you can't have some medical procedure or another because my religious beliefs don't allow it? Let's say you needed heart surgery. I might say, nope, you can't have that, heart surgery is the sign of my evil sky-pixie and no one should ever have it.
What's that? You don't want me telling you what you can do and can't do with your body?
So why the fuck do you insist on telling others what they can do and can't do with their bodies? Why do you insist on imposing your religious beliefs on others with respect to pregnancy or any other decision that involves their body? You don't like it when I do it to you, so why the fuck do you do it to others? Why the fuck can't you keep your religious beliefs to yourself, without insisting that everyone else follow them?