When Lena started to feel unwell late on Monday night with excruciating stomach pains, she put it down to gastro in Brisbane Backpackers.
"I honestly had no idea I was pregnant, none at all. I thought I had a gastro bug," she said yesterday.
"I just remember sitting on the toilet thinking I was going to die from gastro, it was terrible. Then all of a sudden, I pushed and she just came out."
Lena, 37, had been staying at the backpackers for the past few weeks while travelling around Australia.
A few years ago, doctors told Lena she was suffering early menopause and her chances of having children were slim.
She put a small pot belly down to eating a lot of noodles lately.
While Lena might have had the surprise of her life, spare a thought for the two Frenchmen sharing her room who were startled by a crying baby.
Mathieu Caron and Antoine Flinois shared a room with Lena for the past week and had no idea she was pregnant.
"I was working on my laptop, and Lena came into the room, but the light was off so I couldn't see at that stage that she was holding a baby," Mr Caron said. "But then she said to me 'Help, help', so I turned my laptop to light up the room and then I saw the baby."
Mr Caron woke his friend, and together they sat Lena down and called triple-0 for help.
The Frenchmen - who had been in Australia for just over a week - said the events will take a fair bit to beat.
"Wow, it was pretty full on. I was shaking afterwards," Mr Caron said.
At Manly Hospital yesterday, baby Bethany - born a healthy 2.5kg - slept most of the day, oblivious to the chaos her arrival caused.
"I have had absolutely no preparation, none at all ... but it's OK, we'll make it work," Lena said.
Of Bethany's unconventional arrival into the world, there is a constant reminder on the name card attached to her hospital cot.
