Personally, my belief about allowing abortion doesn't really depend on the motivations or sexual promiscuity of the women who get them because it's not about whether they get them, it's about their right to choose.
Very true. That's why asking for evidence on this point is a red herring. It shifts the debate to "convenience vs. need", on assigning fault. This really shouldn't matter to either side.
FWIW, I'm absolutely sure Don is correct on that point. However, that point should be meaningless to both sides of the debate.