A new report has given a shocking glimpse into the hidden prevalence of female genital mutilation (FGM) in Australia, revealing girls as young as five months old are having the procedure.

The study, conducted by researchers at the Australian paediatric surveillance unit at Westmead Children's Hospital in Sydney, found almost 60 girls with FGM had been seen by paediatricians and children's health specialists since 2010, many having undergone the most extreme form of the procedure.

The data provides the first national picture, but is thought to be a gross underestimation of the actual number of cases.

The study's author Elizabeth Elliott, a professor in Paediatrics and Child Health, said of the 59 girls seen with FGM, eight were suffering complications.

"About 20 per cent of them had had infibulation — that is [the] removal of the clitoris — and external genitalia removed and sewing up of the opening," she said.

"Many of these girls were experiencing physical complications such as urinary tract infections, difficulty passing urine, difficulty with menstruation, but a lot of them were also suffering from psychological consequences of having had the procedure," she said.

Professor Elliott said most of the procedures on the girls were performed overseas.

"But we identified three Australian born children, two of whom had had the procedure performed in NSW and one of whom who had been taken to Indonesia to have this procedure performed," she said.

'Don't do it, it's child abuse'

When Sierra Leone woman Fatu Sillah was six years old she suffered horrific genital mutilation.

Professor Elizabeth Elliott said the size of the problem is bigger than the study depicts. ( ABC News: Billy Cooper )

"One of my mother's friends came and got me at my house and took me to their place and pretty much cut me off," Ms Sillah said.

"It took me six months to heal completely and ever since then my life has never been the same."

Since migrating to Australia, Ms Sillah has become educated on FGM and now campaigns publicly against the practice.

She said the study's findings made her angry.

"I feel really, really upset because this culture should have ended ages ago and still today young girls my age and younger are going through this and some people might even die from it, it is just awful," she said.

"Don't do it, don't practice it, and give people funding to fight for this cause, save kid's lives, it's child abuse."

Despite FGM being recognised as physical abuse under Australian law, only 13 of the girls were referred to or were being managed by child protection services.

Most girls were identified in refugee health clinics in major hospitals in Perth and Melbourne, were born in Africa and had the procedure performed in that country.

They ranged in age from 5 months to 18 years old.

Professor Elliot said although she was surprised at the number of cases, the size of the problem in Australia was bigger than the study depicted.

"We really have no idea of the prevalence and we suspect this is a gross underestimate of the number of girls who have been affected by this procedure," she said.

Upskilling of paediatricians and child health specialists needed

Professor Elliot said about 90 per cent of paediatricians and child health specialists surveyed said they would rarely ask about the procedure and about 60 per cent said they rarely examined patients for the procedure.

"One of the key questions for them to ask is 'Has the mother had the procedure done?'. That makes it far more likely that the child will also potentially have the procedure done," she said.

"There needs to be a revision of the policies so paediatricians are well aware of who is at risk, what they should be looking for, how they should be reporting these children to child protection authorities, and what are the legal imperatives involved."

The Royal Australasian College of Physicians said in a statement it "recognises female genital mutilation/cutting (FGMC) as a violation of human rights and has campaigned against the practice for many years. It also is supportive of all paediatricians who actively give voice to this issue".

More than 200 million girls and women worldwide are living with genital mutilation according to the World Health Organisation (WHO).

FGM is a criminal offence in all state and territories of Australia, but prosecutions are rare.

The first successful prosecution over female genital mutilation was in NSW in 2016, when a mother and former midwife and a community leader were convicted over the mutilation of two girls in Wollongong and Sydney's north-west.