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Puberty Blockers are harmful


In 2014, Dr Michelle Telfer of the Royal Children’s Hospital in Melbourne told the Langley family that if their child Isabelle decided to, ‘we can stop this drug, and your body goes back to how it would have been with no long-term consequences". This interaction was broadcast on ABC Four Corners ‘Being Me” 17/11/14

The Langley family, and what Dr Telfer told them in 2014, featured again in ‘A Balancing Act’. However, she is presented as saying to them: ‘We can stop this drug, and your body goes back to how it would have been…’(at12:50). In other words, the phrase ‘with no long-term consequences’ has been cut out.

Because until early 2022, this matters because of recent admissions that the long-term consequences of puberty blockers are unknown. See, for example, the amendments to advice about them made on the UK’s National Health Service website. Up to early June 2020 it read “The effects of treatment with GnRH analogues are considered to be fully reversible, so treatment can usually be stopped at any time after a discussion between you, your child and your MDT.” (emphasis added)


Later in the month, the guidance had been altered to actually reflect how “little is known” and, more importantly, how little has been known:


  • Little is known about the long-term side effects of hormone or puberty blockers in children with gender dysphoria”

  • “Although the Gender Identity Development Service (GIDS) advises this is a physically reversible treatment if stopped, it is not known what the psychological effects may be.

  • “It’s also not known whether hormone blockers affect the development of the teenage brain or children’s bones. Side effects may also include hot flushes, fatigue and mood alterations.” (emphasis added)


The change from describing puberty blockers as “fully reversible” to saying how “little is known” is highly significant. The myth that puberty blockers are reversible seems to coincide with the idea that being diagnosed with gender dysphoria means that one must socially and medically transition.

Puberty blockers are experimental, off label and can cause harm.


ACON's assigns three drugs as "puberty blockers" in Australia for the use of minors, Goserelin, Leuprorelin and Triptorelin. The website advises these medications to be taken periodically 3-5 times per year from 9-11 years old. These drugs however are only approved for endometriosis, chemical castration for men with obsessive sexual desires, prostate cancer and for these conditions their labels advise short treatment periods only, generally 5 months. They are not licensed for adolescent gender dysphoria, their use as ‘puberty blockers’ is off label and nor is it recommended that they be used 3-5 times per year over a number of years on healthy bodies.

Usually, before a drug is even tested on humans, let alone approved for use, animal studies are conducted, there have been three animal studies.

a) Nuruddin, S. et al. (2013)  shows that sheep’s brains are demonstrably altered by puberty blockers Peri-pubertal gonadotropin-releasing hormone analog treatment affects hippocampus gene expression without changing spatial orientation in young sheep.

b) Hough, D. et al, (2017) shows that sheep’s ability to navigate a maze is impaired long after stopping puberty blockers.  ‘A reduction in long-term spatial memory persists after discontinuation of peripubertal GnRH agonist treatment in sheep’.

c) Anacker et al. (2021) demonstrate the dramatic effect of puberty blockers on mice: males develop stronger preference for other males and an increased stress response; females exhibit increased anxiety and despair-like behaviour. ‘Behavioral and neurobiological effects of GnRH agonist treatment in mice: potential implications for puberty suppression in transgender individuals’.

Under normal circumstances such adverse animal findings would halt human trials and preclude their use in humans unless the consequences of not treating were demonstrably worse than the consequences of treating as is the case in precocious puberty and prostate cancer where GnRH agonists are approved under strict conditions and limited period of time.

It appears that ideological pressure has led to normal scientific protocols being overridden. The use of puberty blockers in gender dysphoric children amounts to experimentation and recent reports from the first Gender Clinics in Sweden document serious adverse effects and physical deformities in youth 3-4 years since start of treatment.


We ask you to examine:

Transgender Trend Puberty Blockers - Treatments and Side-Effects  A beginner's primer on puberty blockers by Dr Michael Biggs

William Malone et al.
Puberty Blockers for Gender Dysphoria: The Science Is Far from Settled The Lancet, 2021.

David Pilgrim and Kirsty Entwistle, GnRHa (‘Puberty Blockers’) and Cross Sex Hormones for Children and Adolescents: Informed Consent, Personhood, and Freedom of Expression The New Bioethics 2020


Michael Biggs Puberty Blockers and Suicidality in Adolescents Suffering from Gender Dysphoria, Archives of Sexual Behavior, 2020, pp. 2227-2229.


Michael Biggs Revisiting the Effect of GnRH Analogue Treatment on Bone Mineral Density in Young Adolescents with Gender Dysphoria, Journal of Pediatric Endocrinology and Metabolism, 2021, pp. 937–939.


Society for Evidence Based Gender Medicine New Systematic Reviews of Puberty Blockers and Cross-Sex Hormones Published by NICE


Society for Evidence Based Gender Medicine Sweden’s Karolinska Ends All Use of Puberty Blockers and Cross-Sex Hormones for Minors Outside of Clinical Studies. Concerns over medical harm and uncertain benefits result in a major policy shift

Gender Health Query Medical consequences of hormone blockers

SEGM Finland prioritizes psychotherapy over hormones, and rejects surgeries for gender-dysphoric minors

Transgender Trend Are Puberty Blockers Reversible? The NHS No Longer Says So  Webpage details important shifts in NHS advice re gender dysphoric children and adolescents (accessed 30/6/20)

The BL
Sweden: Hormone treatments for sex change in children causes serious harm, research reveals The Swedish research team, Uppdrag Granskning, revealed that at least 13 children in Stockholm, Sweden, subjected to hormone-blocking treatments to promote their gender change, suffer serious adverse effects and physical deformities.

James Kirkup, “The NHS Has Quietly Changed Its Trans Guidance to Reflect Reality,” The Spectator, June 4, 2020.

        References for the AWW inc's sub-committee's In Defence of Children's Puberty Blocker Flyers:
        Lesbians United produced "Puberty Suppression – Medicine or Malpractice" 
        Medical Damages of Gender Affirming Care
        Online Library of all Puberty Blocker references 
       "Drug used to halt puberty in children may cause lasting health problems

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