In this exclusive clip of Tuesday's Hills episode (watch above), Spencer Pratt worries that his wife Heidi Montag might be pregnant.

He confides in a pal that he took her to Hollywood sushi hot spot Katsuya "for a little alcohol test." He says she didn't even have a sip.

"What if she's already pregnant?" a worried Pratt, 26, asks his pal, adding that if that's the case their marriage is "game over."

The 23-year-old Montag -- who eloped with Pratt just one year ago this month -- has long been vocal about her desire to have kids.

Pratt is so against the idea that he even considered a vasectomy.

He told MTV News in September: "I'm a baby. I'm not prepared. And I'm not sure the world wants a Spencer Pratt spawn."