Stupidity? I don’t think so.
R’ Eliezer Waldenberg permits abortion of a fetus with a life-threatening illness such as Tay-Sachs until the end of the second trimester, and abortion of a fetus with an illness that would cause it to suffer until the end of the first trimester.
The Gemara says that a fetus is considered “mere water” and not an actual life until it is forty days old.