You are mixing "equal" and "same." Would you grant someone a place in a GT program simply because they are pregnant?
It's ok to place kids who learn faster in a GT program, because they're not the same as other kids; but if you wait until a woman gives birth to carry out her death sentence, it's a violation of equal rights? No offense, I just don't see your logic here.
One argument I could understand is that because only women can get pregnant, such a bill provides a loophole for (fertile) women who have been sentenced to death. While that's a valid point, I find it unimportant in the grand scheme of things (due to my view on the point at which life begins), so we would have to agree to disagree.