The GOP would have you tried for murder if you didn't incubate. I'm not sure why you think their stance of not allowing women control of their own bodies would change.
It did brush my mind as I'm still baffled about some abortion laws even if there's no brain development. But if it was an egg, it would be hard to enforce it and some eggs aren't fertilized.
I bet someone would try to outlaw having a miscarriage if they could.