GRINDHOUSE may need significant edits to avoid an NC-17 rating. Page Six has the dirt on some of the more problematic scenes (one example after the jump).
QT had similar problems with Kill Bill – thats why some of the Crazy 88 scene is in black and white (so that the blood is black instead of red). For whatever reason, its OK to hack someone to pieces on screen, just so long as they don’t bleed red blood.

“In one scene, a cute, topless girl is roughly tied down on a table by evil female Nazi experimenters who begin draining her blood and, as she screams in agony, they brand her like livestock with a coal-hot steel swastika,” our source said. “And every girl in the Nazi concentration camp is topless.”