Okay bare with me, I only just started Walking Dead after seeing the show so they may actually go into this in the comics. I've started reading them as well, currently they just got to the prison.
This got me thinking. If everyone is infected and a baby dies in the the womb of a pregnant mother would that baby come back and eat her from the inside? Just the whole zombie apocalypse thing really got me thinking parenthood should really never happen if this were the case especially added the shear danger a baby would put a group in, and the steps leading up to that with the pregnant women.
The remake of Dawn of the Dead kind of touched on this, but the women (Luna) was already a zombie when she gave birth.