if someone had an abortion, would it should up on an autopsy?

No, not for the most part.

Firstly, it would depend on the autopsy - why would they be looking that closely at the uterus?

They may be able to tell she was pregnant via changes to the body if the pregnancy had continued past first trimester, but not that the pregnancy ended in an abortion - remember too that abortion is not always about a person not wanting a child, later term abortions are often carried out because the fetus has already died, so even if they could tell if a person had an abortion they wouldn't know the context (thus no judgement on the person).

The exceptions may be if the abortion had been recent later term abortion, in theory you could see recent uterine scaring from dilation & curettage or dilation & evacuation - to be clear scarring can occur just like with any other area of the body, but the idea that abortion causes perminant scaring and leaves you infertile is largely anti-choice myth.

Consider that most abortions are early abortions, essentially a chemically induced miscarriage so A. it would be early in pregnancy so no real change to the body and B. no way to differentiate between abortion and miscarriage.

maybe, i don't know

actually it might

They would probably be able to tell she had recently been pregnant. It's unlikely they'd be able to tell how the pregnancy ended.