Arnold on affair: Stupidest thing he ever did to Maria

(CBS News) In his first interview since it was revealed that he had a secret child with his housekeeper, Arnold Schwarzenegger tells Lesley Stahl that the affair with Mildred Baena was "the stupidest thing" he ever did to his wife, Maria Shriver. The interview with Schwarzenegger will be broadcast on the 45th season premiere of 60 Minutes, Sunday, Sept. 30 at 7:00 p.m. ET/PT.

Stahl reminds him in the interview how Shriver had given up her career for him. "She gave up her television career for you. I mean, wow! Was this just the most unbelievable act of betrayal to Maria?" Schwarzenegger replies, "I think it was the stupidest thing I've done in the whole relationship. It was terrible. I inflicted tremendous pain on Maria and unbelievable pain on the kids."

The former governor of California has written an autobiography titled, "Total Recall: My Unbelievably True Life Story," in which he notes the affair that resulted in a son named Joseph and writes of another affair he has had outside of his relationship to Shriver. Shriver would not comment to 60 Minutes about the interview or the book, which Schwarzenegger says she has not read.

"She knows that it's about my whole life and that I would not write a book and kind of leave out that part and make people feel like, 'Well, wait a minute. Are we just getting a book about his success stories and not talk about his failures?... I wanted to write a book about me,'" says the former body builder, and action film star who once held the title "Mr. Universe."

The book, out Monday, Oct. 1, from Simon & Schuster, a company owned by CBS, traces Schwarzenegger's life, from poor early years in Austria, to his rise to the top in America in bodybuilding, Hollywood and politics. Stahl also accompanies him back to Thal, Austria, to visit his childhood home.