The NHS has seen a massive upswing of young transgender people who are seeking treatment for gender dysphoria.

London’s Tavistock and Portman NHS Trust, which runs the only clinic in the UK to deal with young transgender people, released its annual figures this week.

It shows that there has been a 500% increase in referrals in the past five years, from 139 in 2010 to 697 in 2014.

There are a growing number of people under the age of 18 who identify as transgender in the UK, but the majority of current gender law only applies to adults.

In addition, the NHS currently bans most gender treatments for those under the age of 16, including most forms of hormone treatment and surgical intervention.

Treatments available for young trans people include ‘hormone blockers’ – which can delay the onset of puberty – as well as psychological services and counselling.

The upswing in youth referrals comes amid a simultaneous crisis in treatment for transgender adults in NHS services, with growing backlogs leaving people waiting years for treatment.

Dr John Dean, chair of the National Clinical Reference Group for Gender Identity Services, warned Sky News: “Not treating people is not a neutral act – it will do harm.

“There are a number of studies that report evidence of suicide and self harm among trans people who are unable to access care.

“It is an intensely demeaning and frustrating experience to have to live in a social role in a body that is incompatible with your deepest inner sense of self.”

Despite an NHS England target that all patients should be seen within 18 weeks, gender services across the country have been under increasing strain – with a leading NHS gender surgeon warning last year that gender identity backlogs are ‘spiralling out of control as the number of referrals outstrips the number of possible appointments.

Health Minister Jane Ellison and Minister for Women and Equalities Nicky Morgan will today give evidence to a Parliamentary Select Committee probing trans issues.