In the UK, prescribing gender affirming hormones to children under the age of 16 incites investigation by the General Medical Council, and a media outcry. In the USA, children as young as 12 are welcomed into ongoing research, with preliminary results showing excellent outcomes.

Dr Johanna Olson-Kennedy, is the Medical Director of the Centre for trans youth and development at Children’s Hospital Los Angeles. The largest trans youth clinic in the US. She is considered an International expert in the medical management of trans youth.

In 2017, Dr Olson-Kennedy published her findings on the early results of the Physiologic Response to Gender-Affirming Hormones Among Transgender Youth.

This article offers preliminary results from a prospective study examining the physiologic impact of gender-affirming (cross-sex) hormones in a cohort of adolescents aged 12–24 years with gender dysphoria, over a period of approximately two years of hormone use.

The authors acknowledge that, ‘Although the presence of primary sex characteristics is often described as a source of distress for transgender youth, the development of “incorrect” secondary sex characteristics during endogenous puberty is the cause of great suffering for many.

In other words, while younger, pre-pubescent gender variant children may experience an element of dysphoria in relation to the presence or absence of certain physical attributes, it is only when secondary sex characteristics start to develop (in males the voice breaking, facial hair developing and the testicles and penis becoming larger, and in females breast growth and periods), that the distress becomes acute.

Those who work with younger gender variant people will often hear transfeminine children talking about the fact that they hate their penis and wish it were gone, or wondering how to get rid of it. They choose their clothes very carefully so that it never shows through. Transmasculine children are more focused on how they might acquire a penis or wondering when theirs might eventually start to grow.

For prepubescent children the sense of dysphoria is often eased when they are able to socially transition, when the child is able to dress either according to their preferred gender or in a more androgynous manner.

They cut or grow their hair, they are left to play in a way which feels most comfortable, alongside children with whom they feel most at ease. In some cases the parents agree to change pronouns or even address the child with their preferred name which reflects the gender with which they identify.

These social steps have been shown to improve the social integration and mental wellbeing of the younger trans child.

However, this can be brought to an abrupt halt when the child begins to develop attributes which bring them physically more in line with their birth gender – and they see themselves ‘developing into’ the gender which for them is the antithesis of who they know themselves to be.

At this stage, distress becomes acute and can impact every facet of the adolescent’s life, at home, school and socially. It tends to be at this stage that patients will come forward for medical intervention so that they can develop the ‘right’ pubertal changes as opposed to the wrong ones.

Here you can read a first hand account of one mother’s experience.

The authors in Dr Johanna Olson-Kennedy’s study on the use of hormones in younger children recognise this, ‘most youth presenting well into endogenous puberty desire hormones to bring their bodies into closer alignment with their gender.’


So who did they include in the study, how were young people aged 12-24 deemed suitable?

Eligibility criteria for the study included (people) aged between 12 and 24 years old, self-identification of an internal gender identity different from the sex assigned at birth, presence of gender dysphoria, a desire to undergo phenotypic gender transition, naivety to cross-sex hormones or less than three months of previous hormone use, and ability to read and comprehend English.


In plain language, this reads:

  • Aged between 12 and 24
  • Self-identification of gender incongruence
  • Distress at the way their bodies were developing
  • Wanting to undergo medical treatment to help their bodies change to match their experienced gender
  • Not been on hormones before (or less than three months of use)
  • Able to understand English language

The authors accept that, ‘Frequent concerns about the safety of hormone use in individuals younger than 18 years can create barriers for youth to access medically necessary interventions that have been demonstrated to improve the lives of transgender adolescents.’

Our objective as medical experts should at all times be to improve outcomes for our patients, whatever their condition.

We know that ‘There is a clear and strong case that delaying treatment risks more harm than providing it.’ and yet in the UK younger gender variant people are actively prevented from accessing hormones until the age of 16.

With limited expertise and experience within the UK, should we not be taking the lead from international centres of excellence where the approach is focused on affirming the patient and helping them to get the best possible treatment to give them the best possible outcomes, as opposed to shutting down alternative views because they may make us feel uncomfortable?

Hear more from Dr Johanna Olson-Kennedy via the GenderGP podcast.


We support trans youth – find out more




Dr Helen Webberley is the founder of GenderGP. A passionate advocate for the transgender community, she continues to campaign for real change in the way that trans people are treated in society and particularly in relation to the barriers they face when accessing healthcare. Dr Webberley believes in gender-affirmative care and that the individual is the expert in their own gender identity.


Photo by Cory Woodward on Unsplash