Dr Caroline Johnson

Dr Caroline Johnson

Conservative — Sleaford and North Hykeham

Speaking in the House of Commons on 23 March 2026

Debate

Puberty Blockers Clinical Trial

Contribution

It is a pleasure to serve under your chairmanship this afternoon, Mr Mundell. I must first declare an interest as an NHS consultant paediatrician. I thank James Esses for the petition and the thousands of people who have signed it, including many of my constituents, for enabling today’s important debate. I also thank the hon. Member for Caithness, Sutherland and Easter Ross (Jamie Stone) for leading the debate so well. The petition asks the Government to cancel the puberty blockers trial and to safeguard vulnerable children. Perhaps it is worth considering whether clinical trials in children are a good idea in principle. The answer, of course, is yes. Children are not just small adults; they have different illnesses from adults, they present with different symptoms and respond differently to medication, and they require different doses at different ages. Properly designed clinical trials ensure that children’s medicines are safe and effective for them. However, today we are discussing one particular trial: a proposal to give puberty blockers—gonadotrophin-releasing hormone analogues—to children, specifically for gender incongruence. Perhaps at this point it is worth considering why doctors and others prescribe medication; we do it to treat or cure disease, to treat or lessen symptoms and to aid in diagnosis. What does this trial seek to do? On the face of it, it seeks to establish whether puberty blockers are a safe and effective treatment for gender incongruence. ICD-11 defines gender incongruence as: “A marked and persistent incongruence between an individual’s experienced gender and the assigned sex”. To suggest persistent incongruence with gender stereotypes is wrong could undo years or decades of rolling back gender norms. If it is not causing the person any distress, why would we want to treat it, especially when we know that most children, even those with gender dysphoria who do have distress, will get better without any puberty blockers? Currently, there is no way to identify which children will persist with a trans identity as adults and which will not. The much-delayed data linkage study could help with that. It could enable more targeted interventions and may also provide information on the long-term outcomes for people who have taken puberty blockers in the past. However, the Government insist on pushing on with the puberty blockers trial anyway, before the data linkage study is complete. Why? In written parliamentary questions, Ministers have said that they expect the data linkage study to be finished by April 2027, so what is the rush? What is the point of the treatment? It has been suggested that it helps transgender adults pass more easily as the opposite sex and potentially avoids surgical operations in adulthood, but how on earth can it be ethically, morally or medically right to treat a large group of children with risky medication to give cosmetic benefits to a much smaller number of adults? There are also cosmetic risks to the treatment. The penis grows very little between the ages of three and 10 years. The use of puberty blockers restricts growth, meaning those with a persistent trans identity may struggle with having enough tissue for a vaginoplasty surgery, and those who do not have a persistent trans identity may struggle with normal intimate relationships. As mentioned earlier, the Secretary of State has said that he has confidence in this trial. Now it has been paused, we can presume that he is not quite so sure. But can we, patients and the general public have confidence in this trial? There are certainly causes for concern. In fact, there are so many that I cannot speak of them all today, but I would like to speak of a few in the time I have available. First, on the selection of patients, we have had a dramatic change in the demographic. There has always been a small number of children uncomfortable in their own bodies, but there has been a rapid increase, which is not fully understood, particularly among girls. Many of them are in care, some have autism spectrum disorders and many are same-sex attracted. We need to understand this before prescribing irreversible treatments. We do prescribe—and I have prescribed—drugs that are high risk or potentially harmful to children. An easy example would be chemotherapy, but that is being given to save a child’s life; it is not used to pause a perfectly normal physiological process in a physically healthy child. The risks of these treatments have been listed today, but I will list just a few: fertility problems; idiopathic intracranial hypertension; demineralisation of bone density, leading to fractures; in some studies, an increase in depression and anxiety; and the long-term loss of sexual function in some patients. We have discussed consent. How do you get consent from a parent of a child—a boy or a girl at Tanner stage 2—about long-term sexual function and fertility? On the design of the trial, it is said to be a randomised controlled trial. Well, it is, but that is a bit of a fudge, because instead of an actual randomised controlled trial where some patients receive puberty blockers and some do not, it has given some now and some slightly later, with a very short difference in the timing. The comparison group that does not have any puberty blockers at all is taken from a slightly different population, which introduces an unnecessary bias. The trial’s organisers have said that they are doing that because they think the children would get the drugs from elsewhere or from abroad, but that is not how we do medical trials. When I have raised this issue, Ministers have responded that it cannot be blinded, but blinding and randomisation are not the same thing. The trial is also far too short to provide data on long-term outcomes. On the process of the trial, the hon. Member for Gower (Tonia Antoniazzi) raised questions about what children are being asked as part of this trial. Why is the trial proposing to ask children about their sexual experiences? Why is this helpful to the trial?

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