Turia Pitt gives birth to her baby boy

Turia Pitt and her fiance have welcomed their first child, with heartwarming photos published online.

Pitt and her fiance Michael Hoskin named their new son Hakavai.

The couple announced Pitt, an athlete and motivational speaker, was pregnant on 60 Minutes in June this year.

Pitt shared the news of the new arrival in an e-newsletter sent out today.

"We'll be in this little newborn bubble for a few weeks,"  she wrote.

"But we wanted to pop our heads out for a moment to share the news directly with you.

"We are totally in love and just so stoked!"

Pitt was horrifically injured in a grass fire while running a 100km ultramarathon in Western Australia in 2011.

She suffered terrible burns to 64 percent of her body, lost seven fingers and underwent more than 200 operations, and faces more yet.

She wore a full-body compression suit for two years afterwards.