Gwen Stefani has been a woman of utter mystery when it comes to her third pregnancy - and, despite her growing belly, she's kept completely mum about whether she had a bun in the oven.

The No Doubt singer already has two sons with husband Gavin Rossdale, Kingston, 7, and Zuma, 5, and a step-daughter in the form of 24-year old model Daisy Lowe, who is Gavin’s daughter from a previous relationship.

And now Gwen has revealed the truth about her growing baby belly.

The songstress posted a picture of herself on Instagram with the caption: “I was ready to hand over the crown. But I guess I am still queen of the house. #itsaboy #surroundedbyboys.”

IT'S A BABY BOY! We bet Kingston and Zuma will love having another brother to play with.

However, while Gwen is ahem no doubt looking forward to welcoming her third son into the family, she did recently admit during a magazine interview that juggling work with motherhood can be tough.

"Being a mom is hard.

"I think a lot of working moms feel that way. [They want] to have time to be themselves as well but it's really hard. There's a price to pay.”

Congratulations Gwen Stefani!