The magic words for me are, "Are we forcing a sapient human being into a parasitical relationship against their will?"
I agree that these are magic words, in that you have conjured them up using your own powers. I understand the argument completely, but am routinely astounded at how someone with this view cannot also see the possibility that the 'parasite' may be entitled to human rights. It's fine to acknowledge both sides and choose - perhaps on aesthetic grounds - to prefer the rights of the mother. But the re-definition of human into parasite is a complete dodge of the (potential) issue.
Yeah, it's really not. A human being is chained into a nine month relationship where another human is draining them of nutrients, altering their body, and putting their life at risk. The closest analogue to that in history is slavery and even that term falls short. I'm going with the term parasite because it covers most of the bases.
Call them human, call them fetuses, call them god's will.
Doesn't matter. What I'm saying is that no human should ever be enslaved to another in that way against their will. If the fetus can be removed, given life support, and live? All power to them. Let's fund that. Otherwise? Tough sh*t.
Edit - In other words, Fenring, can you please detail the human right that is being violated when one human being tells another that they have no right to attach themselves and endanger lives?