One good way to begin any dialogue is to identify who the stakeholders are. In most discussions of abortion, there is only one stakeholder, either the fetus or the woman, or the stake of one is wholly subordinated to that of the other. Positions in which two stakeholders are identified are rare (Roe does this in its own way), and rarely result in agreement, because the various parties refuse to see the issue from the perspective of the other stakeholder.
I would say there is also a third stakeholder in this debate: the family/society that will receive and enrich (or impoverish and threaten) the child once born and, at the same time, be either enriched or threatened thereby. Roe actually identifies this stakeholder as well when it says that the state acquires a right to protect the fetus at viability. 
When we approach this subject as if any of the three stakeholders have absolute rights, we are simply venting and hoping no one will notice how vapid our arguments are.