Radio personality Jackie O says she is a mother-to-be.

The 35-year-old announced on-air today that she is three months pregnant, finally ending the rumours in circulation.

"Regular listeners of this show know how much I have been wanting a baby, that I have been trying to get pregnant, and I just wanted to say this morning, I am pregnant," she told 2Day FM listeners on her morning show with Kyle Sandilands.

"I can say it now, which is great."

Jackie O revealed to the New Idea magazine that she had been helped by IVF after months of trying to fall pregnant naturally.

She told listeners her baby with husband Lee Henderson was due in December.

Sandilands made a joke about the impending birth, saying it had been perfectly planned to coincide with the ratings break period over Christmas.

"You timed it so perfectly, because you knew that there's just no way you wouldn't be able to not be here," he said.

According to Jackie O, Austereo would be setting up a studio in her home so that she'd be able to get back to work after she gives birth.

"I will be able to be back on air more quickly because I can work from home for a while," she said.

She told listeners Sandilands had been quite "teary and emotional" when she broke the news to him, and she has had to go through difficult mornings for the past three months.

"I've had the bad stuff too - including the morning sickness," she said.

"[And] I was so emotional and my mood swings were crazy ... Kyle, so much rage was inside of me sometimes, it was horrible."