You have asked me this before I don't remember what my exact answer was so I'll give it a go again.
I believe that in the interest of consistency, the punishment should probably be that of a mother who kills her days old child. Seems harsh, given that abortion is lawful today but the idea that a yet-to-be born baby is worthy of no protection but killing a newborn can bring life imprisonment just doesn't compute for me.
There is a good alternative to abortion called adoption.