Let’s consider a moral dilemma that does not include an intrinsically evil act.
A woman is pregnant and has been diagnosed with cancer. If she receives treatment for the cancer now, her life will likely be saved, but the treatment will also kill the prenatal. If she delays treatment until the prenatal is viable and is delivered, it will almost certainly be too late to save her life. Which course of action is moral? Is she required to delay treatment, and save the life of the prenatal? May she morally choose to receive the treatment?
This is an example of indirect abortion. The chosen act, treating the mother’s cancer, is ordered toward saving life; it is not ordered toward killing the prenatal. So the death of the innocent is in the consequences only, and not also in the intended end, nor in the object. The act is not intrinsically evil; it is not an act of direct abortion.
The other possible act is to refrain from treatment until the child is viable. This act also has a good intention, to save the prenatal, and it is not intrinsically evil, since the mother is not directly killed by the choice. Her death is merely permitted, not caused. So this act is also not intrinsically evil.
Both acts have the good intention to save life. Both have morally good objects and are not intrinsically evil. The decision then rests on the consequences.
The consequences are very similar in moral weight. One innocent is saved and the other dies, in either case. In both cases, then, the act is moral. It is moral to treat the mother, and it is moral to refrain from treatment and save the child. When faced with a choice between two morally good acts, we are free to choose.
The teaching of the Church on morality does not require the mother to choose to give up her own life, to save the prenatal. Neither choice is required by the moral law.
The mother might willingly give up her life, so that her child may live. I have repeatedly seen news stories of women who faced this real situation, and who chose to give up their lives to save their child’s life. It does happen, and that choice is moral and heroic.
On the other hand, suppose a mother has other children to care for, and she lacks a husband or other relatives who can provide proper care for them. She might morally choose to receive the treatment, so that she can care for her other children, and unfortunately allow the death of her one unborn child. It is a heart-wrenching but moral choice.
However, if the only way to save the mother’s life is to directly kill the prenatal, in a direct abortion, then the act is intrinsically evil and always gravely immoral. The mother may not act to save her own life, if the only way to save her life is to directly kill an innocent. This situation is like the trolley problem, but with only one person on each track. You may not pull the lever, and directly kill the one person to save one other person’s life. If you cannot save innocent life without sinning gravely, then you cannot save that life.
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