According to this, two philosophers named Alberto Giubilini and Francesca Minerva (henceforth to be referred to as G&M) have written a piece published in the Journal of Medical Ethics, which is entitled, "After-birth abortion: why should the baby live?" After-birth abortion is, of course, the killing of a baby AFTER IT IS BORN. This is what these philosophers are justifying. And here are a few of the arguments they use:
1. Both fetuses and newborns do not have the same moral status as actual persons
2. The fact that fetuses and newborns are potential persons is morally irrelevant
3. Adoption isn't always in the best interest of actual people
Their conclusion? Killing newborns should be permissible in every case that abortion is permissible, including when said newborn is perfectly healthy.