A mom who delivered her own baby at high speed on a busy highway in Australia has revealed the dramatic moments that saved the newborn's life.

Mel Sharpe, of southeast Queensland, was in the front passenger seat of her vehicle -- racing at 80mph (130kph) to the hospital on the Sunshine Coast -- when the baby's head crowned.

As she reached down to check, Sharpe discovered the umbilical cord was wrapped twice around the emerging infant's neck. Umbilical cord strangulation is a potentially fatal complication of birth and can also lead to disability.

"When the head came out I felt to make sure there was nothing around his neck because our first son had this issue when he was born," she said. "There was a lot of urgency to get it off.

"I could feel two strands of cord wrapped around his neck. I knew there were two because when I grabbed the cord I could fit my thumb between the two strands."

A professional firefighter, Sharpe drew on her ingrained sense of calm in an emergency and, unable to see what she was doing, managed to flick both cords over the baby's head, with her fiance Adam Geary encouraging her from the driver's seat.

As she cuddled her baby boy, Xavier Aston Geary, Sharpe paused to reflect on how fortunate they were.

"It was very scary because you don't know what could happen," she said. "It had the potential it could have gone the opposite way -- good or bad. I hate to think what the outcome could have been."

The drama did not end when the newborn was free of the cords, however. Sharpe had accidentally snapped the umbilical cord, cutting off the baby's lifeline.

Her fiance had to veer into a roadside gas station, just as Xavier arrived at 3:33am local time, with the couple still some 7.5 miles (12km) from the hospital.

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