Consider the following: Imagine a hunter in the woods who is wanting to shoot a Bambi's mother or father that day. He hears a rustling in the woods, but is UNCERTAIN of whether it is human or not. Does he shoot anyway?
Let's at least be honest about abortion, first. It is terminating another life. For whatever reason, the new entity, with its own unique genetic code, is often viewed as nothing more than tissue. It's a question of ... mindset, and for some I don't think it changes until they see the heartbeat on the sonogram.
Legislative
Legislative proposals may draw upon the principle of maximum life, which governs this area. Let me give an example that will surely put some in a twist, credit to my wife for coming up with this political koane: Would you rather have a baby aborted or adopted by gay parents?
If the baby is going to be killed anyway, why not make adoption as simple as signing an affidavit that one will raise the child has one's own - should be no harder than adopting a puppy, again, if the entity was slated for destruction anyway. Let the child get the money, not the lawyers. This is similar to terminal patients will to have experimental drugs used on them. If they aren't going to make it anyway, shouldn't they have the option?
If the argument of survivability/viability is used, my obstetrician friend in Atlanta informs me that babies now routinely survive even being born at a mere 4.5 months. What distinguishes a child born at that age vs. one still resident in the womb in terms of development?
If done for convenience, then that's a problem, but what is the source? Perhaps abortion is simply a symptom of the real problem. For example, IMO, any such legislation should be paired with a loosening or optimization of adoption restrictions. It has been said, that if every church in Texas had a family that adopted 1 kid, the 40,000 kids in the system would no longer be orphans. I'm working on it, not there yet. Yet it takes thousands of dollars and 7-9 months.
What follows is an example meant to drive up the cost of abortion, apparently: http://www.houstonpress.com/news/aborted-fetuses-must-now-be-buried-cremated-in-texas-8986047
I'm not sure whether it was paired with an effort to drive down the cost of adoption, by removing restrictions.
Exceptions
Then there are the exceptions to the rule --got to have an exceptions process, sorry. For example, Ectopic pregnancy is some scary stuff. In such situations, following the principle of maximum life, if it one life or another or both may be lost, I don't believe it would be proper to compel anyone on which path to take and I'm not competent enough to say what a mother's options might be. There are, of course, other weird situations. The law of unintended consequences is ever present.