The singer, 31, announced the happy news on Twitter on Tuesday, Nov. 19.
“I’m pregnant!!! Brandon and I are so excited! Best early Christmas present ever,” she wrote.
Newly married Clarkson revealed last week in an interview with Jay Leno that she wants to become pregnant as soon as possible, and that she and her husband were trying for it.
“We have two kids. And they’re so great,” the singer told Jay Leno. “I never wanted kids before, but now I want, like, five.”
This will be the first child for the singer and the third for her husband who already has two children, Savannah, 11, and Seth, 7, from his previous marriage with ex-wife Melissa.
The couple got married last month.