Fassbender's relief as injured mom missed Shame screening

Michael Fassbender was secretly pleased his mother missed out on attending a screening of his new movie Shame at the Venice Film Festival - because he was worried about her reaction to his nude scenes.

The X-Men: First Class star plays a sex addict in the upcoming picture, and won the annual European festival's top acting honor in September (11) for the role.

Fassbender had promised to take his mother to the event, but a back injury forced her to pull out of attending - and the actor was relieved.

He tells E! Online, "My mom was supposed to be there, but thank God, her back played up at the last minute. I think it was psychosomatic. Throughout the movie, I was thinking, thank God my mother's not here."

Opening up about the difficulties of tackling the raunchy part, Fassbender adds, "You know, it's always awkward getting naked and masturbating - well, simulating it at least - with a bunch of strangers in the room. But you gotta get over that and get on with the telling of the story.

"The scenes where there are sexual encounters with the characters are so important in terms of where he's at and what his mental state is. It's not about titillation and exploitation."