And yet I don't think that anybody really doubts that the frisky being living and growing in a mother's womb is anything but human. Everybody knows that, and everybody has known it for thousands of years, since the dawn of the Neolithic Revolution. No herding/animal breeding society ever doubted that what's inside a pregnant ewe is a lamb, what's inside a cow is a calf, what's inside a woman is a human child.
We can see it with 4-D sonography, but people knew it in every cognate language that calls a pregnant woman simply a woman "with child."
The problem isn't that people don't know that humans beget humans. The problem is that they don't care.
Information does not provide motivation.
Religious devotion does. I'm not saying you have to be a religious Christian or Jew or Buddhist or Hindu to be pro-life. But it helps.
Yet one thing these 4 women have in common? None has repented their abortions. None are religious, despite each of them supposedly believing in God and identifying as Christian. They think it was just something they did - a long time ago, that had no bearing on their soul, their life, or their trajectory other than to save them from some kind of unmarried mother hell.
You could probably sit down with all 4 of these women, and get nowhere with an argument that they should see themselves as murderers because life begins at conception. They were willing to make that bargain with the devil then, and would probably do so again. I seriously believe that. They leave religion at the door of the Church when (and if) they attend, which isn't often.
It's what I call funcitonal atheism. You can call youself a Christian all you want, but if you only live by Christian principals when it suits you, your belief in God is more something you wear like a hat. And that's not really belief.
So it seems to me, while there are certainly securalists who are pro-life (a great article is here, A Secular Case Against Abortion) - selfishness is such that there are still women who would throw a live baby out of a train before they'd allow it to "ruin" their life - and sadly, in the case of at least 2 of the 4 women I've mentioned, I think they'd probably resort to that if they thought they had to.