The only explanation of the inordinately high figure for thalidomide babies is infanticide. Thus, entry to society takes place at birth. If a major physical abnormality is discovered at that point, one is often denied admission. When Vietnamese Siamese twins come to Japan for surgery, the media give the event lavish coverage. No one asks whether no such babies are born in Japan or, if they are, where they are, probably because people are aware of their fate even though no one talks about it.
Adults are no exception.
Only in 1996 was the infamous Leprosy Prevention Law of 1907 repealed, a law that mandated isolation of people with Hansen's disease from society for life. I imagine Japan is the only country that had a law barring people with a specific disease from society. In Japan, a fetus is not a person. It is part of the mother, so basically its disposition is up to her. When this sense of unity with the mother is extended after birth, we have cases where women kill their children and then themselves.