I just had a flash to some bad 80s horror movie and I have no idea what it was. The scene is a woman who is pregnant or her belly looks pregnant, and a green wormy thing comes out of her belly button. Any ideas??
Xtro is from 1983 and has, in my opinion, the most famous disgusting-birth scene in horror movies. In fact, I’ll spoiler box it because it is pretty much Not-Safe-For-Life. 
Not a bellybutton and not green worm…but a horror movie birth…
I recognize the green worm belly button birth movie. Its on of the later Troma films. It was on USA Up All Night often, but I can’t search for the name right now. But that’s where to look.
[Edit]
A-yup. That’s Troma’s Class of Nuke 'Em High
Cronenberg’s The Fly? There’s an abortion scene with a maggot birth that has scarred me for life.
Yes! Thank you!
I think so!
Still, check out that Xtro birth. It was INSANE.