The former tennis star and the singer are already parents to twins Lucy and Nicholas, and are now thought to have another on the way.
Anna, 38, was recently pictured in Spain’s Hola! magazine looking heavily pregnant on board a boat in Miami.
While she and long-term partner Enrique, 44, haven’t confirmed the news, her huge bump seemed to.
The couple are known for being fiercely private, and this isn’t the first time they’ve kept a pregnancy under wraps.
When Anna was pregnant with their twins, they kept the whole thing a secret until days after the little ones were born.
Hero hitmaker Enrique has spoken previously about his new life as a father and how he hopes he’s a cool dad.
He once said: “It’s one of the best feelings in the world. [I’m more responsible]. I drive slower. I think about stupid things a few more times before doing them.
“I hope to be a cool, easy-going dad.”
Anna and Enrique have been in a relationship since 2001 after they met on the set of his Escape music video.
Enrique has kept his personal life to himself throughout his years in the spotlight, but he does share adorable pictures of his children on Instagram every now and again.
He’s also spoken about his romance with the sportswoman, saying there’s no such thing as a “perfect” relationship.
He said: “You go through your good times, you go through your bad times. It’s a tough thing for me to believe there’s such a thing as the perfect relationship. I don’t think that exists.
“Firstly, she’s the coolest girl in the world. And she understands who I am, to the point where she’s willing to sacrifice her personal time with me and let me do my music. It’s a huge sacrifice and I respect that tremendously.”
Mirror Online has contacted Anna and Enrique’s representatives for comment.
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