The couple, who already have three-year-old daughter Blue Ivy together, are feeling incredibly "lucky" over their apparent impending arrival, reports femalefirst.co.uk.

"They've been trying for a while, and it was so hard when it wasn't happening. They both desperately wanted another child and feel so lucky. But they definitely won't tell everyone with just a statement, that's not their vibe," a source told OK! magazine.

The "Drunk in love" hitmaker is also believed to be worried about "jinxing" things by revealing they are expecting ahead of the first trimester.

The source added: "Even though she's barely showing, she's paranoid that someone will pick up on it, so she's hiding her stomach whenever she goes out.

"They've gone through so much to get here that they don't want to jinx it by telling everyone before the three-month mark. They'd love to involve Blue, because they know how much she wants a little brother or sister."