More than 70 women and girls in the UK are seeking treatment every month for problems linked to female genital mutilation.
According to the NSPCC, 1,700 victims have been referred to specialist clinics in the last two years, a number likely to be a fraction of the total affected by the practice.
A girl of seven was the youngest victim, reported the BBC.
The "illegal and life-threatening initiation ritual", common to some African, Asian and Middle Eastern communities in the UK, can leave young victims in agony and with physical and psychological problems that can continue into adulthood, the charity said.
The partial or total removal of female genital organs is often performed without anaesthetic, with victims suffering extreme pain.
A new helpline is being launched by the NSPCC with the support of the Metropolitan Police and the Royal College of Midwives to combat what they said is an abusive practice being carried out on young girls and even babies.
Women who have had FGM carried out on them as babies often don't realise they have been mutilated until they become pregnant or have repeated infections and abdominal pain.
Lisa Harker, the NSPCC's head of strategy, said: "The UK's child victims of female genital mutilation are hidden behind a wall of silence.
"Like other forms of abuse if female genital mutilation is not exposed it will continue to thrive and more children will suffer.
"Children who are at risk or victims of female genital mutilation often don't even know it is abusive and harmful because it is done at the request of their family.
"They are told they are unclean and immoral if they are not 'cut' and that it is in their best interest.
"There is also a huge pressure within these communities to keep quiet about female genital mutilation, with some people even being threatened with violence if they speak out.
"This is why we believe a dedicated helpline with specially trained child protection advisers is needed to help overcome the difficulties in protecting children from such a complex and secretive form of abuse."
The free 24-hour helpline on 0800 028 3550 and dedicated email address fgmhelp@nspcc.org.uk is aimed at anyone concerned that a child's welfare is at risk because of female genital mutilation and wanting advice, information or support, the charity said.
This includes the children themselves, parents, other relatives but also professionals working with at-risk families.
Though callers' details can remain anonymous, any information that could protect a child from abuse will be passed to the police or social services.
Detective Chief Superintendent Keith Niven, of Scotland Yard's sexual offences, exploitation and child abuse command, said: "The Metropolitan Police Service is committed to supporting survivors of FGM and bringing to justice those responsible for committing this horrific crime.
"This practice cannot be disguised as being part of any culture, it is child abuse and offenders will be relentlessly pursued."
Janet Fyle, professional policy adviser at the Royal College of Midwives, added: "We welcome the introduction of a service that provides confidential and independent advice to vulnerable young girls at risk of FGM.
"FGM is child abuse and we want midwives and other health workers, who are on the frontline of safeguarding and protecting girls and young women, to seek information and advice if they are concerned about a young girl or child."