"I do not know the answer to this question, is it the policy/requirement to be pro-life for a mom in this condition to give up her life per these circumstances?"
these are the odd situations. unfortunately this is probably a real connundrum for a catholic, which is the worse cardinal sin, abortion or suicide?
personally, i believe she made the right choice. i told my fiancee that in a choice between her and our child, the only way that she would win was if there was absolutely no way the child would survive in any case. and of course, same goes for me, child comes first.
The question is: even if she had received the treatment for the cancer, would she have lived? There is not guarantee on that. But, by waiting for treatment until the baby could be delivered, she guaranteed at least one of them lived.
There is no such requirement.
Assume for the sake of argument that the woman had uterine cancer. Then an act which has as its primary object the saving of the woman's life (a hysterectomy) would have as a necessary consequence the concommitant effect of killing her unborn child.
Since the evil averted is equivalent to the (secondary) evil resulting necessarily from the same act, the primary act is judged to be morally permissible (under the principle of double-effect).
An action that is good in itself that has two effects--an intended and otherwise not reasonably attainable good effect, and an unintended yet foreseen evil effect--is licit, provided there is a due proportion between the intended good and the permitted evil.
The Catholic church teaches that direct, deliberate abortion (intended to kill the child) is to be judged the same as any other deliberate killing of a human being, that is, it is wrong whether as a means to an end, or as an end in itself.
The baby's life is considered equal in value to the mother's life (or the father's, or the Queen of England's for that matter): neither more nor less.
Since the doctor has an equal obligation to save the mother and the baby, if the baby is save-able at all, then he has to try to save both.
That's not always possible, but it has to be the intention.
The most common solution is to try to deliver the baby prematurely, as early as possible, consistent with its survival, and then treat the mother's cancer as aggressively as you have to with radiation, chemo, surgery or whatever.
In rare circumstances (tubal pregnancy, but other cases as well) --- especially if the situation is such that the baby won't survive no matter what you do--- you can surgically remove the mother's pregnant but diseased organ (fallopian tube, uterus or whatever) and bring about what is called a "double effect": the baby perishes, but it was perishing in its mother anyway, so it is not considered "killing" the baby if you act to save the mother in this way.
I hope I have not made this seem too complicated. The principle is simple. (1) You try to save both. (2) If is is strictly not possible to save both,then you do what you need to do to save the one you can.