It's pretty simple, until the child is out of the womb, it's not a child. There is no overarching negative consequence if you abort that child.
There is an extremely negative consequence if you try to regulate a person who is a grown persons body.
I would only buy the argument of respecting a life if we also extend this to way beyond a child in the womb, and to everyone living. Until we do that, there's no excuse to control a person's body.
Just last night, my wife and I had a peek into the current home of our 15-week-along child. He or she was so active - wiggling and squirming, no doubt as a result of some of the prodding from the midwife. I saw arms and legs moving, fingers, feet and everything. Their heart beating at 140bpm. My other children live in the environment of our house, and this child lives in the environment of the womb. It is simple: this is a child. The consequence of killing him or her would be massive to them - ending the life which I was blessed enough to peek into for a few moments. The debate rages with passion because people are passionate about the subject - I know I am.
How would you feel if in week 16 a complication arose which meant that unless your child is aborted, your wife will die, along with your child? What choice would you make then? What if you couldn't make any choice at all, and you had to say goodbye to your wife knowing that if you lived under a different law, she'd be allowed to choose to live?
Again, this is why it's the choice of the person carrying it.
You don't want to, no one is forcing you to abort.
The discussion here is "who is forced to do something". This child in the womb would not be able to live without the life of the mother. Therefore their "choice", if you can even call it that, is irrelevant.
Why stop there? A child about to be born is structurally and functionally identical to a child that has just been born. And once it is born, there are, as you say, "extremely negative consequences" to forcing the mother to either care for it herself or make other arrangements.
The right to dispose of any unwanted child the mother cannot or will not care for herself is one that, like in vivo abortion, women will exercise irrespective of whether the law permits it. Poor indigenous women in Brazil allow their sickly babies to starve all the time.
Conclusion: any society that does not allow humane infanticide within the first year is literally Handmaid's Tale.
There is an extremely negative consequence if you try to regulate a person who is a grown persons body.
I would only buy the argument of respecting a life if we also extend this to way beyond a child in the womb, and to everyone living. Until we do that, there's no excuse to control a person's body.