Mark Zuckerberg
Mark Zuckerberg announced on Facebook that he and wife Priscilla Chan are expecting their first child together Facebook / Mark Zuckerberg

Mark Zuckerberg has confirmed that he and his wife Priscilla Chan are expecting their first child together.

The Facebook founder turned to social media to share the happy news with his 33 million "friends" with a 'pregnancy announcement.'

Posting a picture of his wife and her baby bump on his own Facebook page, he revealed the couple are expecting a baby girl.

Priscilla and I have some exciting news: we're expecting a baby girl!
- Mark Zuckerberg

"Priscilla and I have some exciting news: we're expecting a baby girl!" the 31-year-old wrote. "'This will be a new chapter in our lives. We've already been so fortunate for the opportunity to touch people's lives around the world - Cilla as a doctor and educator, and me through this community and philanthropy. Now we'll focus on making the world a better place for our child and the next generation."

While it remains to be seen whether the baby will inherit billionaire Zuckerberg's entrepreneurial spirit, he is already convinced she takes after him. He revealed that a scan appeared to show the baby giving a thumbs-up sign reminiscent of a Facebook 'like'.

"Cilla and our child are both healthy, I'm extremely excited to meet her and our dog Beast has no idea what's coming. In our ultrasound, she even gave me a thumbs up 'like' with her hand, so I'm already convinced she takes after me."

Opening up about the couple's struggle to get pregnant he revealed that he and his wife have been trying to have a baby for a few years and that Priscilla suffered three heartbreaking miscarriages.

Zuckerberg said they wanted to share their emotional story to help others who face the same struggle alone.

"We want to share one experience to start. We've been trying to have a child for a couple of years and have had three miscarriages along the way. You feel so hopeful when you learn you're going to have a child," he wrote. "You start imagining who they'll become and dreaming of hopes for their future. You start making plans, and then they're gone. It's a lonely experience.

"Most people don't discuss miscarriages because you worry your problems will distance you or reflect upon you - as if you're defective or did something to cause this. So you struggle on your own.

"When we started talking to our friends, we realised how frequently this happened - that many people we knew had similar issues and that nearly all had healthy children after all.

"We hope that sharing our experience will give more people the same hope we felt and will help more people feel comfortable sharing their stories as well. Our good news is that our pregnancy is now far enough along that the risk of loss is very low and we are very hopeful."

"We're looking forward to welcoming her into the world and sharing more soon when she's ready to come out and meet everyone!"

Zuckerberg and Chan met at university in 2003. They married seven years later on May 19, 2012 in a quiet ceremony in their backyard.

They announced their nuptials - like their pregnancy - with a post on Facebook.

Zuckerberg, whose net worth is estimated at $34.8billion, is the 16th richest person in the world according to Forbes.