It is possible to defend this logically - provided you don't bring religion into it.
If you believe that as soon as a sperm fuses with an egg you have life and, thus, a human being, and that the life of that human being is equal with the life of all human beings, then abortion is insupportable...
That won't help if you are pregnant because your father or brother raped you. If you have been, Alabama will now force you to carry the child to term. Praise the lord.
So you think this is the fault of women?
The answer is the same as the answer to the question "why don't moderate labour supporters, supposing they are unhappy with their momentum-supporting elected representatives, vote some moderates into office?". The anser is women/moderates/whatever need...