Representatives of the couple broke the news.
Crowned the Sexiest Man Alive by People magazine in November, the actor had recently admitted in an interview that a baby was on their mind.
"I'm ready. I think she's ready," Tatum had said in an interview, adding: "The first number that pops into my head is three, but I just want one to be healthy and then we'll see where we go after that."
The couple wed in Malibu in 2009.