To me, it all comes down to the amount of overall suffering

The first three months the fetus is incapable of feeling pain because it doesn't have a functional spinal cord or significant brain development. Plus three months should give most mothers plenty of time to soul search and find out whether they want to keep it or not. After three months and the brain develops and the fetus can start feeling pain and suffering, I think it should only be terminated in cases of extreme health to the mother, otherwise it's unnecessary suffering and cruelty to the would-be child.