Gender Incongruence: Puberty Suppressing Hormones

Caroline Johnson Excerpts

Wednesday 30th April 2025 Westminster Hall

[Dr Caroline Johnson (Sleaford and North Hykeham) (Con)]

It is a pleasure to serve under your chairmanship, Ms Lewell. I start by making a declaration of interest as an NHS consultant paediatrician and a member of the Royal College of Paediatrics and Child Health. My work in the NHS at times involves looking after children who may have gender dysphoria, although it is not specifically for that purpose. I congratulate my hon. Friend the Member for Reigate (Rebecca Paul) on securing this important debate, and on her excellent speech.

Hippocrates’ dictum, “first do no harm”—although it does not actually appear in the Hippocratic oath—captures a core medical ethic, and is an important guiding principle in policymaking. When it comes to children and young people expressing gender dysphoria, we must take a compassionate but firmly evidence-based approach. The causes of gender incongruence are not fully understood, but they are likely to be multifactorial and influenced by both biological and social factors. It is of huge concern that diagnoses of gender dysphoria have risen over fiftyfold, and that vulnerable and same-sex attracted children are over-represented.

There are legitimate licensed uses for puberty blockers, such as in cases of children who enter puberty very young, and in the treatment of certain malignancies. However, using puberty blockers for young people with gender dysphoria represents a significantly different context, both medically and ethically. With most children with gender dysphoria, symptoms resolve without treatment, with many finding that the natural process of puberty leads to a resolution to their distress.

The Gender Identity Development Service began trialling puberty blockers for adolescents with gender dysphoria back in 2011. Preliminary findings in 2015-16 showed no psychological benefit from the treatment and, alarmingly, a deterioration of wellbeing in some children, particularly some girls. The Cass review, published last year, showed that there is insufficient evidence on the long-term effects of using puberty blockers to treat gender incongruence. I ask the Minister: why does the planned trial not look at long-term outcomes?

The Cass review made the risks of these drugs explicit. Puberty blockers can seriously compromise bone density and can lead to adverse long-term neurodevelopmental effects. As for the purported benefits, the review added that,

“no changes in gender dysphoria or body satisfaction were demonstrated.”

The often repeated justification that blockers are for “time to think” was not supported by the evidence, with concern that they may instead alter the developmental trajectory of psychosexual and gender identity.

In May 2024, the last Government passed emergency legislation to temporarily ban puberty blockers for new treatments of gender dysphoria. The current Government have renewed that order twice, continuing restrictions until the end of this year. However, that does not affect cross-sex hormones. Does the Minister plan to commission research on the outcome of masculinising and feminising hormones on young people? Do the Government plan to extend the ban to cross-sex hormones in the fullness of time?

We heard in February that the NHS has announced plans to start offering puberty blockers as part of a clinical trial. There are questions about this trial. Given that most children’s symptoms will resolve anyway, and that the Cass review clearly states there is no method of proving in advance which children will have improved symptomatology and which will not, the trial will be essentially treating a whole cohort of healthy children with drugs to see the effect on the around 15% whose symptoms may not resolve in adulthood. Former Tavistock clinicians, including David Bell, have said that they would not refer patients to the clinical trial.

The Government are taking direct control of NHS England, so it is now the Secretary of State’s responsibility to ensure that any such trial is properly conducted. The gold standard for a medical trial is the double-blind randomised controlled trial. Will the Minister confirm that if the trial goes ahead there will be a control sample? The trial still requires ethical approval from the Health Research Authority. Will the Minister provide an update on when that decision is expected, clarify how the Government are ensuring the impartiality and safety of the decision-makers, and clarify whether provisions are in place to pause or suspend the trial if safety concerns arise?

[Sir John Hayes]

Might my hon. Friend add to her list of questions and ask about the experience of other countries that have looked at these matters? For those countries that have used alternatives to having children in trials, how effective have such alternatives been?

[Dr Johnson]

My right hon. Friend raises important questions that I hope the Minister will answer. It is important to look at the data that we already have. That was the next part of my speech—my right hon. Friend is, as usual, reading my mind.

Given that these drugs have been used on hundreds of patients at GIDS alone, why not look at that data, rather than conduct new experiments on further children? Despite the last Government legislating to ensure that data could be made available for research, several NHS trusts refused to participate fully in the Cass review. What are the Government doing to retrieve that data and to ensure that NHS trusts, which are now more directly controlled by the Government, comply with data-sharing requirements in the future? If the trial does go ahead, how will the Secretary of State ensure the genuine impartiality of those conducting the trial so that we can rely on the results?

In conclusion, this debate is about the wellbeing of young people. Gender-questioning children are not solely defined by their gender incongruence and gender-related distress; they are whole individuals. They deserve holistic care and the same rigorous evidence-based care as any other young patient.