When Anthea Nicholas found out she was pregnant, like many expectant mothers, she burst into tears.
"As soon as I found out I cried," she told news.com.au.
Were they happy or sad tears? "Terrified tears," she said.
Anthea, 55, and her husband Pete, 59, never expected they would become parents. They met later in life and both agreed that having children wasn't for them. "I just thought I was too old," Anthea said.
Doctors advised the couple against using contraception, because Anthea's age and Pete's low sperm count meant the chances of falling pregnant were two million to one. The chances of her successfully carrying a child to term were even lower - seven million to one.
But in 2010, at age 50, Anthea realised she had fallen pregnant naturally.
"We were advised by both our GP and our obstetrician to terminate the pregnancy. We had to give it some serious consideration, but Pete was stronger than I was and felt really blessed," she said.
In 2011, she gave birth to her son Nick, who is now five.
"Now I look at Nick and he's such a gorgeous, healthy boy. It's so nice. Can he chuck a tantrum in Coles? Of course. But he's a very sweet kid."
Anthea is the oldest Australian woman to give birth after falling pregnant naturally.
In August, a 62-year-old Tasmanian woman became Australia's oldest mother after giving birth to a daughter conceived via IVF. Her partner is 78 years old.
At the time, AMA president Dr Michael Gannon labelled the couple's decision as "madness", "selfish" and "wrong".
An Indian couple in their 70s celebrated the arrival of their first child in May, almost 47 years after getting married.
Daljinder Kaur, 72 and Mohinder Singh Gill, 79, made headlines around the world - and were also labelled selfish - for their decision to receive IVF treatment so late in life.
The list of female celebrities aged 40 and over who have fallen pregnant is hard to ignore: There's Janet Jackson (49), Michelle Bridges (44), Kelly Preston and Geena Davis (both 48), Halle Berry (46) and David Bowie's wife Iman (45). Many of these women have used younger, donor eggs.
The debate about older parents rages on as advances in IVF technology mean women over 40 are increasingly turning to modern medicine to fall pregnant.
It's an issue explored on SBS's Insight program, where older parents and their children are interviewed about their experiences.
Anthea, who appears on the show, has always been "genuinely concerned" about her son having older parents.
"We continue to be active, healthy parents, but it's making sure he gets the physical activity he needs when he doesn't have siblings to run around with. We want to make sure he has plenty of exposure to other kids," she said.
"We would love to be able to adopt so Nick has a sibling, but it's just impossible. Our age legally denies us the right to apply, because 50 is the cut off."
While organising play dates and running around after a five-year-old isn't how Anthea planned on spending her later years, having a child has been a blessing in disguise.
"We stand over his bed at night and just say to ourselves 'We've been really lucky'. There will always be a percentage of people who say 'No, you shouldn't have done that'.
"But my pregnancy was unplanned. Should I have terminated it? I recently had an intense conversation with a woman who thought I should have, and at the end she said, 'You haven't changed my mind about it, but I understand where you're coming from'."
What's Anthea's favourite thing about being a parent? "The ability to see things through the eye of a child, because you forget how to do that."
And the worst? "The noise. I learned to say goodbye to quiet, private time a long time ago."