The most famous eugenicists were the Spartans. Their newborns were allowed to live only if perfectly healthy. The state did not want to be burdened by imperfect babies.
The modern eugenicists advocate infanticide as being no different than abortion. According to an article in The Telegraph, a team of medical ethicists linked to Oxford University maintained that “parents should be allowed to have their newborn babies killed because they are ‘morally irrelevant.’ (Stephen Adams, February 29, 2012)