You still haven’t got it.
You know “direct abortion” is an ethical construct not a visible medical procedure don’t you?
You know that “medically necessary” is also a hidden ethical proposition as well surely?
No medical procedure is actually objectively necessary. Only a moral judgement makes it so.
Which begs the very question you ask.
Try and construct a sentence without the ambiguous word “abortion.”
You will find that you cannot.
I think your paradox rests on your use of “abortion” with two contradictory meanings in your mind.
(one medical, one ethical). Like the infinitely circular staircase teenagers like to draw.
you can say death of the child is medically necessary to save the mother.
Then the ethical issue is can that be done morally.
You know the answer.
Therefore if it is done morally it is not direct abortion.
If it was not done morally then somebody’s intention was not of the required quality (perhaps they were glad it was ectopic cos they didn’t want the child anyways so were happy to kill it).
This might be considered direct abortion re the mother.
The Catholic surgeon would likely not be committing a direct abortion but a morally good act of saving the mother.
You see the morality is not primarily in the procedure but in the agent’s intent.
The type of procedure has a bearing though.
Some “procedures” can never anchor a good intent (killing of the innocent).
And some “procedures” can never, in themselves, anchor a mortally sinful intent (light theft, a small lie).
Perhaps the sort of question you ask is like this:
Is it ever necessary to kill the innocent?
Then you have to define what you mean by “necessary”.
Do you mean ethically good? You know the answer.
Do you mean you are forced by the expectations of others as to what is ethical?
If one is forced to do something it is no longer a full human act on your part.
Only human acts can be moral (I mean either morally good or bad).
You are again confusing “procedures” (external human actions) with intent.
So if we are talking of force (whether external or internal) then we say such acts have mitigated culpability. Choosing the “procedure” is still “disordered” and objectivelywrong. But they are only personal venial sins or maybe not even that. We did not have full intent.