Kyle Sandilands rushes off air mid-show to welcome his son Otto with fiancée Tegan Kynaston

Kyle Sandilands has welcomed his newborn son, Otto, with his fiancée Tegan Kynaston.

The breakfast radio shock jock was on-air broadcasting from home and about to introduce co-host Jackie O's news segment when he abruptly announced e had to leave the show.

"I am broadcasting from home for a reason, and that reason seems to have raised its head now. I think I might have to leave the show and go to the hospital,” he said.

"Oh it's time," Jackie gleefully declared as the studio burst into cheers and applause.

Kyle Sandilands

"Calm down, we don’t want the kid coming too soon," Sandilands joked before telling Jackie and their staff, "Guys, I’m so sorry. I feel very unprepared.

"I’ve got to run… I feel like I’m abandoning you, but I’m there for my child," the father-to-be said before make dashing off to the hospital in time for his son's birth.

Stepping in for the rest of the Kyle and Jackie O show with Jackie was KIIS FM producer Pedro Cuccovillo Vitola.

Later in the show, Jackie - who is god mother to the newborn - was overcome with emotion as she announced to listeners that Otto had been born.

She said: "Tegan’s really healthy, the baby’s healthy. I'll read the text, I got this from Kyle’s manager Bruno, 'little Otto born this morning mum and bub both doing well. Kyle’s beyond excited and he will jump on tomorrow's show to chat all things Otto'." 

Intern Pete (Kyle and Jackie O producer and reporter Peter Deppeler) later spoke to Kyle in the hospital car park after the birth.

The new dad didn't shy away from giving listeners a graphic retelling of the birth, he said: "Otto's born, Otto's fabulous. I cut the cord, I didn't realise it was like tough calamari and blood squirted out.

"Mum is doing great, he's happy, he's up there breastfeeding. I'm watching Karl on the Today show. Everything's good," Sandilands added.

Sandilands first broke the news that he and fiancé Tegan were expecting their first child together on the Kyle and Jackie O show in February.

See also: Shock Jock: Kyle Sandilands is expecting his first baby at age 50

Kyle and Tegan