Fergie is about to get a new hump.

The singer has announced on Twitter that she is pregnant with her first child with husband Josh Duhamel.

"Josh & Me & BABY makes three!" she wrote on February 18.

Apparently, the couple just learned the thrilling news recently.

"They just found out and tweeted it to the world," a source tell Us Weekly.

The couple spoke to Oprah in October about their desire to start a family, with Josh — whose film, Safe Haven, opened on Friday — admitting to wanting more kids than Fergie does.

"We negotiated that early on," Fergie, who's 37 years old, said. "Two is our number."

We're so excited for them! And we hope Fergie and Josh get plenty of sleep now: Big girls may not cry, but babies certainly do!

Congrats, you two! 

Sources: TwitterUs Weekly