On 21 November the Ministry of Health released its long awaited position statement, accompanied by an evidence brief, on the safety and long-term impacts of puberty blockers (a non-medical intervention) when used in the context of gender-affirming care:
Puberty blockers evidence brief.
The document is not official government policy. Nor does it claim to be either a clinical analysis of (or a guideline about) the use of puberty blockers. Further, the information it is based on is confined to up to September 2023.
After considering and citing much material it concludes that the evidence about the impact of puberty blockers on clinical and mental health and wellbeing outcomes is scarce; that evidence which is available is “largely of poor quality.”
In no small part this is because studies “…generally rely on small, localised cohorts, making it difficult to extrapolate to other, larger cohorts.” Further:
Given the dearth and poor quality of evidence, and New Zealand-specific evidence, there is an urgent need for high-quality, longitudinal data and research to help us understand the specific needs of gender-dysphoric adolescents in New Zealand.
Hippocratic Oath
The Health Ministry’s position statement provides a starting point for the development of robust guidelines over the prescribing of puberty blockers. In this context it is a welcome document.
It also resonates with my earlier Otaihanga Second Opinion post on puberty blockers (26 September):
Puberty blockers and the Hippocratic Oath – Otaihanga Second Opinion
I argued that the approach to what is known as the Cass Review of puberty blockers in the United Kingdom should be seen through the lens of the Hippocratic Oath (first do no harm).

Hippocrates’ oath still relevant today
This is not an anti-trans rights lens. I have previously posted twice in my politics blog Political Bytes my support for trans rights and opposition to anti-trans bigotry (links to both are in my above-mentioned puberty blockers post).
It is also the right of all people to have the treatments they might receive for whatever condition to be consistent with the Hippocratic Oath.
This includes the right of young trans people to evidence and experience based guidelines on puberty blockers that includes being seen through a medical lens (I use the term medical to include all branches of medicine including psychiatry and general practice).
Cautionary article
Epidemiologist Emeritus Professor Charlotte Paul (Otago University) along with two colleagues (Simon Tegg and Sarah Donovan) have written a ‘must read’ cautionary article on the use of puberty blockers for children and young people with gender dysphoria published in the New Zealand Medical Journal (27 September):

Emeritus Professor Charlotte Paul and colleagues issue timely caution over puberty blockers
They note that the prevalence of prescribing puberty-blocking hormones generally (not just gender dysphoria) in Aotearoa New Zealand increased from 2011 (when the first national guidelines were published) to 2016 and then more steeply from 2016 to 2022, before declining.
The rapidity of this prescribing increase from 2016 was most marked among those aged 12–17 years (a more than threefold increase) which the authors very largely attribute to use for gender dysphoria.
Prevalence
The difference in prevalence was even more marked compared to England and Wales up to 2020, such that New Zealand had 6.9 times the cumulative incidence of prescribing.
By 2021 government imposed restrictions were introduced following the High Court judgement on the Tavistock controversy in the United Kingdom.
Paul and her colleagues identify several difficulties in making comparisons between Aotearoa and other countries because of differences in methodologies.
Further, data on prescribing puberty blockers for gender dysphoria is not always disaggregated from prescribing for other non-controversial purposes.
Nevertheless they are confident that the finding of much higher prescribing in New Zealand is robust notwithstanding not having the exact figure.

Prescribed puberty blockers now 11 times higher than England and Wales
Current prevalence of the use of puberty blockers in New Zealand is now 11 times higher than in England and Wales compared with 6.9 in 2020. The authors attribute this to a sharp decline in use following the judicial review of treatment practices in 2020.
Why is prescribing so high in New Zealand
Their article also asks an obvious question; why is prescribing so high in New Zealand and why has it increased so rapidly?
One possibility might be a steeper rise in the prevalence of adolescent gender dysphoria or transgender identity in New Zealand. But there is no evidence for a rise in transgender identity from 2012 to 2019.
On the other hand, the authors highlight “a strikingly high proportion of girls” aged 12 years in 2021-22 who reported a non-binary or transgender identity (8.2% of natal girls and 1.5% of natal boys) suggesting “a very recent increase among children.”
The main reasons given for higher prescribing of puberty blockers are considered to be found in New Zealand’s health system. The authors suggest these reasons might be:
- easier access to assessment;
- a lower threshold for diagnosis of gender dysphoria; or
- greater likelihood of recommending treatment through puberty blockers for those with gender dysphoria.
The article also reports decline in prescribing from 2021. If it is not a “chance occurrence” it could be, the authors tentatively suggests that health professionals and parents may be becoming aware of more cautious approaches overseas to prescribing puberty blockers for gender dysphoria.
However; beware of transphobic influences
This article by Professor Paul and her colleagues is broadly consistent with the Ministry of Health’s above-discussed evidence-based position paper. It also resonates with my own above-mentioned concerns.

Dr Rona Carol: A ‘must read’ timely caution about the influence of transphobia
Dr Rona Carroll, Senior Lecturer in Primary Health Care and General Practice at Otago University has, however, written a timely caution published The Conversation(5 December):
Dr Carol is experienced in the prescribing of puberty blockers for gender dysphoria. She is concerned that public rather than medical consultation risks opening up to decisions being influenced by bigoted misinformation from vociferous transphobes.

Brian Tamaki at forefront of vociferous transphobia
Transphobia comes predominantly from the far right such as Brian Tamaki’s Destiny Church. But it also includes some who consider themselves part of the political left (but not representative of it).
Within the National-ACT-NZ First coalition government, transphobia is more visibly discernible within NZ First.
Consequently Dr Carol is right to be concerned. Further, she also raises another valid but related concern. While the Health Ministry’s focus is on the risks of puberty blockers, it does not consider the benefits. She is well placed to understand these benefits.
What we need and don’t need
Dr Carol supports medically based regulations but warns about the detrimental health effects of bans or non-medically based restrictions.
Both the Health Ministry position paper and Professor Paul’s published article are compelling. While not intended as such, I consider them to be complementary.
Aotearoa needs robust medically based guidelines consistent with the Hippocratic Oath for the prescription of puberty blockers to help young people suffering gender dysphoria.
What we don’t need is this process being derailed by transphobia. Ministry and Minister of Health; please take note!
Ian Powell was Executive Director of the Association of Salaried Medical Specialists, the professional union representing senior doctors and dentists in New Zealand, for over 30 years, until December 2019. He is now a health systems, labour market, and political commentator living in the small river estuary community of Otaihanga (the place by the tide). First published at Otaihanga Second Opinion
It’s possible that New Zealand’s very high incidence of puberty blockers and other gender dysphoria treatments, could emanate from the gender confusion and anxiety triggered by a school curriculum promulgating to young children that they can choose their own gender, that they may have been born in the wrong body, and ergo that they may not be who they think they are. This is a rotten thing to do to children, and in itself could be a direct cause of gender dysphoria, messing up kids’ lives, and potentially criminalising parents who unsurprisingly, query the dynamics and then get dubbed transphobic when their primary concern may be the well-being of their children.
If you tell people something often enough some of them will end up believing it and children can learn quickly although they usually don’t have the discernment to sort fact from fiction. Relying on their parents to enlighten them is probably the biggest problem when you consider the wide ability levels among parents.
Bonnie When there are primary school teachers telling 7- 8 year old pupils that their classmate Fred is now a dress-wearing girl called Fiona, it adds to the confusion and pressure put on kids, and on their respective parents. When Fiona continues to whack others in the solar plexus in a non-feminine sort of way and other girls try to avoid Fiona at playtime, chaos can ensue. This is happening.
Prolific puberty-blocker prescribers justify doing so saying that these children threaten to commit suicide if they don’t get them. Sadly, many transgender people do go on to take their own lives anyway, and it seems that gender dysphoria goes hand-in-hand with other mental health conditions and it may not in fact be the primary issue, or the most appropriate one to be prioritising.
Yes. It obviously is a case where the state must act in loco parentis. And telling little boys who for whatever reason are prone to homosexual urges that chopping their cock off will make them attractive to men, and little girls that they can avoid the embarrassment and confusion of puberty by ‘becoming male’, is just plain bad parenting.
Quite right!!
Ian – Thank you for a great post…Thankfully, the tide is turning against this medical experiment.
I agree that the guidelines should be based on medical decisions, and the Cass Review includes the best evidence to date. Charlotte Paul is also provides good info on the topic.
I also agree that there is transphobia around, except that many people accuse others of transphobia, merely for objecting to the use of puberty blockers for gender confusion in young children, or for recognising that no-one can actually change sex. Sex (male or female) is set at conception and begins developing in utero. It can’t be changed by hormones or surgery – those modify some secondary sex characteristics, but not the primary ones.
Puberty is a crucial stage of development from child to adult, and a lot of important changes (in the brain, bones and sexuality etc) occur during that period. It is window that closes after a certain amount of time. Blocking it means risking some important development may never happen.
I agree the likes of Brian Tamaki is anti anyone not conforming to sex-based stereotypes, and is also homophobic.
But Rona Carroll is one of the people who has been involved in the development of NZ’s guidelines to date as part of NZ’s PATHA. The Cass Review found the PATHA guidelines to be of poor quality.
The problem now is that we can’t trust the groups that have previously promoted the guidelines resulting in the over-prescribing of puberty blockers. And these lobby groups are firmly embedded in political, medical and other influential organisations. They have been highly censorious of anyone question the past use of puberty blockers (eg within the NZ Green Party). Many medical people are afraid to speak out publicly with any criticisms of puberty blockers.
So that makes it necessary to open up consultation to the wider public to break the strangle-hold of those who have been involved in the over-prescribing and misrepresentation of what they alleged was the evidence for puberty blockers.
Charlotte Paul, emeritus professor of preventive and social medicine at the University of Otago, on puberty blockers:
‘A whole new group of children and young people are suffering gender dysphoria: do we know what we are treating and would it resolve without treatment?
‘The condition is not new. But before the past 10 years it was rare and largely confined to boys who developed it early in life. Recently, it has become more common among natal girls – developing dysphoria around the time of puberty. Cass concluded the recent surge in dysphoria among natal girls could not be explained by increasing social acceptability of underlying trans identities. Instead, she pointed to social media and social stresses – and as a manifestation of broader mental health challenges.
‘Before medical treatment was available, most children grew out of gender dysphoria. But most of those given puberty blockers don’t and go on to cross-sex hormones. Thus, puberty suppression may alter the trajectory of development of gender identity.’
https://archive.ph/tuti3
The Greens, most of whom are thick, seemed to have escalated this issue because of one poor immigrant being prayed over to stop him being gay, and not even in New Zealand. The outcome of the state usurping parental rights is disgraceful.
Great thanks. I am not and have never been anti-trans just as I was never anti homosexuality and indeed was on the streets to push for law change. I am really horrified about our use of puberty blockers. I am also concerned about this as a ‘fashion’ I just simply don’t believe there are thousands of kids with this dilemma. But what do I know I am not living with a kid who isn’t sure what gender they are. I watched a doco from the US where a couple didn’t assign a gender to their child (who had male genitalia), the child would make up their own mind the parents said and one day came home from pre-school I think it was and said I’m a boy….. give me strength.
It will be interesting to see how much longer medical professional indemnity insurers will offer doctors cover in this area. The malpractice claims for the surgery have already started overseas.
Puberty blockers aren’t surgery.
Chemical castration isn’t surgery either but it has the same effect as cutting off ya balls. Puberty blockers are just as destructive to a growing body as surgery and in some ways much worse.
Cheers for the article, Ian – it’s always great to hear your info and ideas.