There is a moral judgment involved in determining that interrupting pregnancy is good, while interrupting cancer or pneumonia is bad. At the most basic level, it’s the judgment that continuing to live is good, while dying is bad. Almost everyone makes that judgment about himself - life good/death bad - at all times.
True. But the judgment is that ending life is wrong, not interrupting a natural process.
BTW, contraception also interrupts a natural process. Most non-Catholic conservatives don’t therefore believe it to be wrong.
I have no data on Cherokee attitudes towards birth control. :)