Heidi Montag and Spencer Pratt welcomed their first child, a boy, on Sunday, the couple's representative announced.
"Heidi and Spencer are proud parents of a healthy baby boy as of this afternoon," the rep said.
Montag confirmed the news on Twitter.
She gave birth to Gunner at 3:06 p.m. He weighed 6 pounds, 12 ounces and was 19 inches long.
Montag announced her pregnancy in April, and confirmed the next month that she and Pratt are expecting a baby boy. She said in an interview with Us Weekly that it was "in [her] heart" to have a son.
"I thought Spencer really used to want a boy, and then a few months ago we had a conversation where he said, 'Let's just make sure it's healthy. Boy or girl, I don't care,'" the star recalled.
Montag appeared on the MTV series "Laguna Beach" before starring with Pratt on "The Hills."
Her former co-star Lauren Conrad welcomed her first child, Liam James, with husband William Tell in July.