My caveat is that medically necessary abortions to save the life of the mother or if the baby is non-viable are legal up to the point the professionals involved deem it necessary
Only if the child's been disobedient. So it's actually not acceptable until AT LEAST 9 months, because how's a fetus gonna disobey? But after that for however long the parents are alive. This is lindy.
Clarity: I'm assuming you mean only voluntary abortion.
Clarity: I'm assuming you are strictly considering a personal case of voluntary abortion.
If either assumption is wrong, my answer would also change.
Also; I can never be pregnant, so... My view here is very stunted.
Question doesn't really capture the gradient of reasons necessary to justify the abortion. I think, roughly:
up to 3 months: no questions asked
up to 6 months: needs specific justifications
up to 9 months: probably only medical emergencies or significant disabilities/defects
I always start from extremes – if you're at 9 months and you have a Savita Halappanavar situation, then how do you conclude the abortion is not morally okay? Circumstances matter more than the trimester.