Nick Lachey, 38, announced on Live! With Kelly this morning, as he co-hosted the show, that he and wife Vanessa Minnillo are expecting their first child.

Lachey told the audience that after Vanessa appeared on the show in early January, "she started to feel a little different, not herself. So she went to the store, got a pregnancy test, and it came back positive. So we are having a baby!"

Vanessa, 31, is due in the late summer or early fall. The couple, who was married last year, doesn't yet know the sex of the baby. Nick told Kelly: "We definitely want to know. I can't take the knowledge that someone out there knows, but I don't know. It's like watching a sports game on TiVo."

The former boy-bander said of the good news: "I've had a chance to do a lot of great things in my career and my life but this is the one thing that, more than any other, I look forward to. The fact that it's actually here, it's overwhelming."