Every Catholic parliamentarian must vote according their well-formed conscience. I would say just this. I believe it is sufficient because - I say well-formed because it is not the conscience of 'what seems to me.'
Pope Francis[Abortion] is an evil in and of itself, but it is not a religious evil in the beginning, no, it's a human evil. Then obviously, as with every human evil, each killing is condemned.
Pope FrancisThe fruits of this profound union with Jesus are marvelous: our whole being is transformed by the grace of the Holy Spirit: soul, intelligence, will, affections and even the body, because we are united in body and spirit.
Pope Francis