There are many things most people would rather not dwell upon when considering the facts behind the marriage between Heidi Montag and Spencer Pratt, perhaps the most reviled pairing in reality TV.

Thank God sex isn’t really a fact in their marriage, according to Pratt.

Pratt, 26, said that he’s tried to prevent Montag, 23, from realizing her dreams of becoming a young mother — by refusing her sex.

“I’m not even kidding, my wife — OK, I’m gonna get crass here — but we’re barely having sex because I’m scared that she’s gonna have a baby,” he said. “That’s the level our marriage is on right now. I’m not even kidding — my wife has me debating cutting off my nuts.”

Behind his abstinence is his fear that Montag might go off her birth control without telling him, he said.

“She’s not the kind of person who would lie — she would just walk away and not answer the question,” he said. “So yes, I’m very concerned. Our sex life has dramatically changed recently.”