Which has historically often been the case, says Susi Fox, whose psychological thriller, Mine, looks at the idea from a number of angles.

Sasha, the protagonist, wakes up in a hospital bed. She's had a caesarean but there is no sign of her baby, or her husband. A flash of a memory of being put to sleep, of blood, of doctors. When the nurse finally takes her to the tiny baby, hours later, Sasha knows with a certainty that the baby is not hers.

But no one believes her. And without giving the ending away, as a reader, you're never sure who to believe either.

Fox, 40, wanted the book, her first novel, to explore the ways in which women aren't often believed, or even heard, when they do speak up.

"Not being believed is a frightening place to be," Fox says.

She's been a doctor for 16 years and has seen first-hand how women are treated differently by the medical system.

"The research shows that women are treated differently," she says, "from pain management, where women are more likely to be treated with sedatives than analgesics to the diagnosis of heart disease where much of the research is based on how men present."

Fox didn't set out to write a medical thriller – and Mine is much more than that – but said being able to use her knowledge of the medical system and how it sometimes works was an advantage.

The idea for the story came to her in a dream.

"I had this dream where I was holding a baby in my arms and there was a group of faceless people surrounding me," she says.

"I was showing the baby to them and saying this is not my baby and no one believed me and they walked away.

"When I woke up my heart was pounding and I was quite distressed. It was more of a nightmare than a dream and it lingered with me, haunted me, for weeks."

She attended a writers' retreat for doctors not long after and there the story flowed.

Writing has always been a part of Fox's life. She did a combined medicine and arts degree at the University of Melbourne and is studying "very part-time" for an associate degree in professional writing and editing at RMIT. In 2014 she received a Varuna Fellowship and was part of the 2015 Queensland Writers Centre/Hachette manuscript-development program.

She's not keen to discuss her own children, but knows first-hand about the struggles of new motherhood, both in her practice and through her work with local mothers' groups in regional Victoria.

"I wanted to explore the idea of how new mothers can be particularly hard on themselves, how women can be very judgmental of each other, how often we don't support each other enough."

While in the maternity ward, Sasha meets several other new mothers who are dealing with their own problems, from premature babies, to postnatal depression and perhaps even postpartum psychosis. Each makes the other question their own decisions and choices.

When Fox decided to expand her dream into a full story, she was surprised at how common baby swaps still are despite all the checks put into place in modern hospitals.

"Mix-ups, errors, mistakes, are part of being human and that's the conclusion I came to over the course of writing the book," she says.

"No matter how good the system there will always be a chance of human error."

By the end of the book you're still unsure whether an error has been made.

"It's a problematic ending, a very morally ambiguous ending," Fox says.

"I wouldn't have made that decision that Sasha made but it seemed the only possible way to do it.

"We should ask ourselves if women are allowed to make mistakes, if women are allowed to make decisions that we don't agree with, and why we judge them for that."