When a so-called medical professional is trained and skilled in decapitating a human, snipping her delicate, half-developed spine with scissors, dismembering her with long-handled forceps and scalpels, and then suctioning out every last trace of the "clump of cells", that sort of takes a moral toll on them.
For Kermit Gosnell, it was only a logical progression for him. He routinely performed "late-term abortions", that is, children who were capable of surviving, and living well, outside the womb. So Gosnell once in a while had a dilemma where a child would be delivered, still alive, still breathing and begging to live. Gosnell's impeccable medical training took charge of the situation, and he snipped her spine and tossed her into the Biohazard Bin all the same.
Kermit Gosnell benefited immensely from technology. He had ultrasound to guide him so he could perform a "safe abortion", that is, not harm the mother physically while he ripped the infant out of her belly. He had sterile tools and an autoclave where he and his staff could easily clean the blood and gore off the instruments so that they would not infect the next mother, or Gosnell himself. Isn't technology wonderful? That big ol' Biohazard Bin and the Stericycle Van that came to pick up barrels full of human remains, they have good technology too; their supply chains are down to a science, and they will clean up any serial killer evidence that Gosnell might have left behind. If only Gosnell would've done something about the adult witnesses.