Say a woman has brain cancer, and doctors tell her that they have to operate quickly and give her medication/radiation/chimo that would very likely the fetus. In this case, the principle of double-effect is in place, therefore, it would be morally justifiable to have the surgery, because it is not directly intended that the fetus be killed. Moreover, to do nothing would kill them both.
But…what if a woman is told that she has time to deliver the baby first, before receiving treatment, but that by the time she delivers the baby, the cancer would spread enough that it would be too late to save her? I imagine Catholic moralists would say that she would have to wait to deliver the child, and then die of the cancer…unless I’m wrong here?