You didn't answer what they asked. They asked how often is a baby killed right in the moment before birth. I think this is a bit of disconnect when thinking about what abortion is. Abortion is ending pregnancy. If a woman is giving birth, the pregnancy is ending. There's no "abortion" how you're thinking about it.

The abortions after 20 weeks are for the fetuses that have severe defects that we can't detect before the anatomy scan. With our current technology we cannot detect these defects before 20 weeks. It's impossible. These fetuses are the ones who don't have a brain, whose brain stems are exposed, whose organs fused with the placenta, whose hearts never develop, etc. There's not many of each type of deformity, but when you add them up, they account for "late term abortions". And just as an fyi that is not a medical term. It's a political one.