He's referring to Kermit Gosnell, a Philadelphia abortion doctor who ran an incredibly gruesome, dangerous, and unethical medical practice that apparently included "abortions" for viable infants; he basically built a practice that victimized poor residents of Philadelphia.

I agree that Gosnell got less coverage than it merited, although the motivation for that goes both ways: since a powerful majority of the country supports legal access to abortion, you could argue that Fox News avoided the story because it underscored the lack of availability of safe, ethical reproductive health services to the poor of this country, which is something the state-level Republican parties are campaigning against.

The Wikipedia article is pretty thorough and well-cited:

https://en.wikipedia.org/wiki/Kermit_Gosnell

Without being combatant: it's usually best to quickly use Wikipedia and a search engine before asking for a reference in cases like this.