NICE review echoes concerns raised by experts: poor evidence base for puberty blockers and cross-sex hormones

Many clinicians have now raised concerns about the use of puberty blockers in children, particularly in the last few years. Much of the unease of these medical professionals has been about the lack of evidence for their use, their efficacy and their safety, and many of them have been criticised for raising their concerns. 

But they were right to keep speaking out, and the NICE evidence review does much to validate their concerns: there isn’t a solid evidence base, and those studies which do exist are unreliable, subject to bias and produce results of low certainty. 

In 2005, a GIDS report by Dr David Taylor suggested that young people need to be able to explore different options before being prescribed puberty blockers.

In 2017 a GIDS report by Dr David Bell highlighted concerns of clinicians that children were being prescribed experimental drugs after minimal consultation. For speaking out against the practices at GIDS, Dr Bell faced disciplinary action from the Tavistock and Portman NHS Trust.

In January 2019, three doctors wrote to the RCPCH journal Archives of Disease in Childhood, expressing their concerns about the use of puberty blockers in children and adolescents, calling it a ‘momentous step in the dark’. They raised queries over whether arresting puberty might consolidate gender identity, may have an adverse effect on the maturation of the adolescent brain and that puberty blockers were being used ‘in the context of profound scientific ignorance’. 

In February 2019, Professor Carl Heneghan and Tom Jefferson wrote in the BMJ expressing similar concerns about the use of puberty suppression. They concluded:

“The development of these interventions should, therefore, occur in the context of research, and treatments for under 18 gender dysphoric children and adolescents remain largely experimental. There are a large number of unanswered questions that include the age at start, reversibility; adverse events, long term effects on mental health, quality of life, bone mineral density, osteoporosis in later life and cognition.”

In December 2020, a Judicial Review found puberty blockers are accurately described as an experimental treatment to which under 16s are unlikely to be able to give informed consent (the case is subject to an appeal to be heard in June 2021). Part of the evidence provided to the court showed that with very few exceptions, those children and adolescents who commence on puberty suppressing medication will continue on to cross-sex hormones, again raising the concern that puberty suppression may solidify gender identity.

“A momentous step in the dark.”

Richards, Maxwell and McCune, Archives of Disease in Childhood (2019)

As part of the independent review into gender identity services for children and young people, NICE undertook an assessment of the clinical effectiveness, safety and cost-effectiveness of the use of puberty blockers and cross-sex hormones  (which NICE refer to as ‘gender-affirming hormones’) in children and adolescents. Oestradiol, triptorelin (the puberty blocker used in the UK) and most testosterone preparations are not licensed for use in gender dysphoria, and therefore are being used ‘off-label’ in children and adolescents.

NICE is an independent organisation responsible for driving up standards in the health and social care systems. They produce guidelines and quality standards with the aim of improving outcomes for patients and are internationally renowned for their rigorous and systematic reviews of evidence.

This week, after some delay, the reports on this analysis have been published and the conclusions confirm the concerns of medical professionals as outlined above: there is no solid evidence base for the efficacy or safety of puberty blockers or cross-sex hormones in children and adolescents. 

The main conclusions of the report in to puberty blockers states:

“The results of the studies that reported impact on the critical outcomes of gender dysphoria and mental health(depression, anger and anxiety), and the important outcomes of body image and psychosocial impact (global and psychosocial functioning), in children and adolescents with gender dysphoria are of very low certainty… They suggest little change with GnRH analogues from baseline to follow-up.”

They go on to say:

“Studies that found differences in outcomes could represent changes that are either of questionable clinical value, or the studies themselves are not reliable and changes could be due to confounding, bias or chance.”

With puberty blockers being heralded as life-changing and ‘life-saving’, we would expect to see a raft of conclusive results, showing just how great an effect they have. However, this comprehensive review has found no solid evidence to back up these claims. This is quite a surprise as puberty blockers were first used for gender dysphoria in the late 1990s, giving clinicians over twenty years to gather and publish the evidence on their effectiveness. 

The NICE reports into cross-sex hormones and puberty blockers both draw similar conclusions: all studies produced evidence of low quality or certainty. No studies compared cross-sex hormones or puberty blockers with a control group (the gold standard for clinical research), and all follow-up periods for cross-sex hormones were relatively short. NICE states that “further studies with a longer follow-up are needed to determine the long-term effect of gender-affirming hormones for children and adolescents with gender dysphoria.” They caution that “it is not clear whether any changes seen were due to gender-affirming hormones or other treatments the participants may have received.”

Examples of drugs whose prescribing is based on a scant, poor or biased evidence base, resulting in significant harm to often vulnerable individuals, are not hard to find. Opioids, benzodiazepines and antidepressants are just a few of the more well-known drugs which have made headlines in recent years. 

It is becoming more likely that puberty blockers and CSH in children and young people will join this infamous group. 

We hope the Cass Review will take a thorough and careful look at the pathways and treatments being offered to children and young people who are in psychological distress. This NICE review of the evidence will feed into that review, and should give anyone pause for thought about whether this truly is the panacea that many charities, healthcare and social support services would have us believe. 

“It is not clear whether any changes seen were due to gender-affirming hormones or other treatments the participants may have received.”

NICE evidence review (October 2020)

Our children deserve the best care possible. At present, the evidence does not show that this is what they are being offered, let alone receiving. This review has shown that the clinicians involved in ‘gender-affirmative care’ are not basing their practice on robust evidence, nor conducting robust research into the best ways to help gender-confused children and young people. There have been over two decades in which to gather evidence of the effectiveness of these treatments, and questions need to be asked as to why detailed, long term follow up with clear expectations of the outcomes of treatment has not happened. There seems to be the emergence of only one solution: a medical pathway, with or without the evidence to support it. 

NICE Evidence Review on  Puberty Blockers  

NICE Evidence Review on Cross Sex Hormones