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Ministry of Health Evidence Brief on Puberty Blockers

Updated: Sep 5, 2023

The following is a letter that Speak Up for Women sent to the Minister of Health, we copied the letter to other interested parties.

Diana Sarfati, The Director General of Health

Shane Reti, Opposition Spokesperson for Health

Matt Doocey, Opposition Spokesperson for Mental Health

September 4 2023

Dear Minister

Re: Ministry of Health Evidence Brief on Puberty Blockers

Speak Up for Women (SUFW) welcomes the news that the Ministry of Health is broadening the scope of its evidence brief on GnRH agonists (puberty blockers) to include studies regarding mental health and wellbeing outcomes. However, given that a number of other countries have already conducted recent evidence reviews in this area, we are concerned by the Ministry’s statement that this broadening of scope is going to delay the release of this evidence brief by a number of months.

Given the importance of this brief on the treatment of distressed and confused children and young people in New Zealand, we would like to take this opportunity to highlight the recent evidence-based findings completed by other countries’ health agencies or other independent organisations and/or researchers. This is particularly important given a number of researchers and clinicians in this area who claim that puberty blockers provide mental health and/or wellbeing benefits but who have significant conflicts of interest. This includes, but is not limited to, medical organisations and researchers (particularly in the US) who have received funding from pharmaceutical companies that manufacture medicines used to blockade puberty, and clinicians who blockade the puberty of patients as their primary treatment pathway and have a direct interest in their current practices being affirmed.

We note that the countries that have completed research (including systematic reviews that are considered the gold standard) have all concluded that puberty blocker use is not well evidenced, that in general the risks outweigh any potential benefits (including mental health benefits), that other methods of care need to be pursued first, and that medical interventions should be confined to research settings and/or be subject to ethical approval for each individual.

A summary of the studies completed to date and key excerpts from their findings is below:

1. Sweden National Board of Health & Welfare (NBHW), 2022

“The Swedish Agency for Health Technology Assessment and Assessment of Social Services (SBU) concludes that existing scientific evidence is insufficient for assessing the effects of puberty suppress-ing and gender-affirming hormone therapy on gender dysphoria, psychosocial health and quality of life of adolescents with gender dysphoria [2]. Knowledge gaps need to be addressed and the National Board of Health and Welfare recommends that these treatments be provided in the context of research.”

“At group level (i.e. for the group of adolescents with gender dysphoria, as a whole), the National Board of Health and Welfare currently assesses that the risks of puberty blockers and gender-affirming treatment are likely to outweigh the expected benefits of these treatments. The National Board of Health and Welfare therefore gives the following weak, negative recommendations as guidance to the healthcare system:

• Treatment with GnRH analogues, gender-affirming hormones, and mastectomy can be administered in exceptional cases.

Care must be provided on the basis of scientific evidence and proven experience and according to the principle of doing good and not harm. In revising its recommendations, the National Board of Health and Welfare has taken account of the fact that the efficacy and safety, benefits and risks of treatments are not proven.”

“The new recommendations entail that a larger proportion than before, among adolescents with gender incongruence referred for diagnostic assessment of gender dysphoria, will need to be offered other care than hormonal treatments.”

2. UK National Health Service (NHS) Implementing advice from the Cass Review June 2023

After an evidence review, NHS determined that “gender incongruence [usually] does not persist into adolescence,” that “psychological support” and “a watchful approach” are generally recommended instead of “social transition” due to its “risks,” and that puberty blockers/cross-sex hormones will only be given to minors in a research study.

3. The Cass Review Interim Report (Independent expert review commissioned by UK Government)

“In the short-term, puberty blockers may have a range of side effects such as headaches, hot flushes, weight gain, tiredness, low mood and anxiety, all of which may make day-to-day functioning more difficult for a child or young person who is already experiencing distress. Short-term reduction in bone density is a well-recognised side effect, but data is weak and inconclusive regarding the long-term musculoskeletal impact.

“A closely linked concern is the unknown impacts on development, maturation and cognition if a child or young person is not exposed to the physical, psychological, physiological, neurochemical and sexual changes that accompany adolescent hormone surges. It is known that adolescence is a period of significant changes in brain structure, function and connectivity. During this period, the brain strengthens some connections (myelination) and cuts back on others (synaptic pruning). There is maturation and development of frontal lobe functions which control decision making, emotional regulation, judgement and planning ability.”

4. National Institute for Health and Care Excellence (NICE) Evidence review, 2020a (UK)

The NICE evidence review on GnRH agonists (puberty blockers) major finding is that GnRH agonists lead to little or no change in gender dysphoria, mental health, body image and psychosocial functioning. In the few studies that did report change, the results could be attributable to bias or chance, or were deemed unreliable. The landmark Dutch study by De Vries et al. (2011) was considered “at high risk of bias,” and of “poor quality overall.” The reviewers suggested that findings of no change may in practice be clinically significant, in view of the possibility that study subjects’ distress might otherwise have increased. The reviewers cautioned that all the studies evaluated had results of “very low” certainty, and were subject to bias and confounding factors.

“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 using modified GRADE. They suggest little change with GnRH analogues from baseline to follow-up. The studies on puberty blockers “are of very low certainty [i.e., quality] using the G.R.A.D.E. rating system... As the studies all lack appropriate control [groups], any positive changes could be a regression to [the] mean.” The G.R.A.D.E. rating system is the most widely adopted tool for grading the quality of [research] evidence.”

5. Finland Board for Selection of Choices for Health Care (PALKO / COHERE Finland), 2020 SEGM

“Medical Treatment Methods for Dysphoria Related to Gender Variance in Minors”

“In a larger study consisting of 201 adolescents, 101 patients with the average age of 15.5 (12-18 years) started an 18-month psychological supportive intervention, and, additionally at six months, pubertal development was suppressed by starting GnRH analogue treatment. The other cohort of 100 only received psychological supportive intervention for 18 months. In both groups, statistically significant increases in global psychosocial functioning were found at 12 and 18 months; among those having received psychological intervention alone, the improvement in global functioning was already significant at the 6-month mark. Both studies lack long-term treatment follow-up into adulthood.”

“The first-line treatment for gender dysphoria is psychosocial support and, as necessary, psychotherapy and treatment of possible comorbid psychiatric disorders. In adolescents, psychiatric disorders and developmental difficulties may predispose a young person to the onset of gender dysphoria. These young people should receive treatment for their mental and behavioural health issues, and their mental health must be stable prior to the determination of their gender identity.”

6. Denmark Joins the List of Countries That Have Sharply Restricted Youth Gender Transitions” (SEGM)

“Following systematic reviews of evidence conducted in Europe and the subsequent reversal of the “gender-affirmation” paradigm in favor of a cautious, developmentally-informed approach that prioritizes psychosocial support and noninvasive resolution of gender distress in Sweden and Finland, Denmark appears to have made a quiet but resolute shift to treat most youth presenting with gender dysphoria with supportive counseling rather than puberty blockers, hormones, or surgery. In 2022, only 6% of those referred to Denmark’s centralized gender clinic were prescribed endocrine interventions (puberty blockers and/or cross-sex hormones).”

“Most youth referred to the centralized gender clinic no longer get a prescription for puberty blockers, hormones or surgery—instead they receive therapeutic counseling and support.”

7. Sweden’s Karolinska Ends All Use of Puberty Blockers and Cross-Sex Hormones for Minors Outside of Clinical Studies (SEGM)

The Karolinska Hospital in Sweden recently issued a new policy statement regarding treatment of gender-dysphoric minors. This policy, affecting Karolinska's pediatric gender services at Astrid Lindgren Children's Hospital (ALB), has ended the practice of prescribing puberty blockers and cross-sex hormones to gender-dysphoric patients under the age of 18.

According to Karolinska’s newest policy, which went into effect in May 2021, going forward, hormonal (puberty blocking and cross-sex hormone) interventions for gender-dysphoric minors may only be provided in a research setting approved by Sweden’s ethics review board. The policy states that careful assessment of the patient’s maturity level must be conducted to determine if the patient is capable of providing meaningful informed consent.

There is also a requirement that patients and guardians are provided with adequate disclosures of the risks and uncertainties of this treatment pathway. It is not clear whether minors under the age of 16 would be eligible for such trials.

The Karolinska Hospital’s new policies echo a growing international concern over the proliferation of medical interventions that have a low certainty of benefits, while carrying a significant potential for medical harm. The latest policy issued by the Karolinska cites the UK NICE evidence review, which found the risk / benefit ratio of hormonal interventions for minors highly uncertain; the 2020 UK judicial review, which highlighted the overarching ethical problems with the practice of medical "affirmation" of minors; as well as Sweden's own Health and Technology Assessment (SBU) evidence review conducted in 2019, which found a lack of evidence for medical treatments, and a lack of explanation for the sharp increase in the numbers of adolescents presenting with gender dysphoria in recent years.

8. Puberty Blockers for Children: Can They Consent?

Highlights weaknesses of researcher claiming positive mental health benefits:

Turban (Citation 2020) in a paper on the risk of suicidal ideation in young people given PBs concluded that suicidal ideation was reduced in those who had PBs. There are however serious weaknesses in their methodology: they derived the information from a voluntary survey of transgender adults in the U.S. Excluded from this sample of 89 respondents were people who had PBs and then de-transitioned. Any who had committed suicide were of course omitted. Most had started taking PBs after the age of 17 (when puberty would have been well advanced). Since PBs are generally given only to those who are aged 12–16, this means the respondents did not represent the group which is the focus of this review, and is therefore of limited relevance to consent in under 16s.

“It is concluded that children are unable to consent to the use of puberty blockers.”

We hope that this information is helpful and that the Ministry of Health is able to release its expanded evidence brief without undue delay.

Suzanne Levy

Speak Up for Women



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