Where did the 'fact' that puberty blockers are reversible come from?

The effects of puberty blockers are reversible. If a person stops taking puberty blockers, the effects of puberty will return or resume. That's what reversible means in this context.

Ah you're right - I thought it was a typo in the post I quoted but it was in there twice. Bloody clear explanation though!

The key passage is this:

"Cohen-Kettenis had two collaborators at Amsterdam. One was Henriette Delemarre-van de Waal, a pediatric endocrinologist. She had expertise using the new GnRHa drugs—developed in the 1980s—to treat precocious puberty and other conditions (e.g. Schroor et al. Citation 1995)."
...
"The Dutch protocol comprised not just a drug (GnRHa) and a treatment regime (from age 12 or Tanner stage 2) but also two discursive claims. The first was reversibility. The initial article declared GnRHa to be “fully reversible; in other words, no lasting undesired effects are to be expected” (Gooren & Delemarre-van de Waal, Citation1996, p. 72). The phrasing hinted at the lack of actual evidence. Suppressing puberty for a short time, on the order of months, might be expected to have a negligible effect on a child’s development. Yet the Dutch protocol entailed suppression for up to four years (from age 12 to 16); for FG it lasted at least five years (from 13 to 18).

It was implausible to claim that suppressing puberty for so many years would have no lasting effect if the child were to stop GnRHa and restart their natal sex hormones. On occasion this was acknowledged, as when Delemarre-van de Waal and Cohen-Kettenis’ (Citation 2006, p. S137) manifesto stated that “It is not clear yet how pubertal suppression will influence brain development.”

Ten years later, however, Cohen-Kettenis still claimed that puberty suppression was “completely reversible” (Cohen-Kettenis, Citation2016; see also de Vries et al., Citation2016). The postulate of reversibility, however implausible, helped to avoid the question of whether a child aged 12 (or below) could give consent to this endocrinological experiment. HBIGDA’s Standards of Care warned that cross-sex hormones “are not, or are not readily, reversible” (HBIGDA, Citation1985, p. 83). By pronouncing GnRHa to be reversible, the Dutch protocol demarcated a boundary between one endocrinological intervention and another.

This may be interesting reading: www.tandfonline.com/doi/full/10.1080/0092623X.2022.2121238

The interview with the Dutch protocol clinicians on the Gender A wider lens podcast is also fascinating.

What I think the data does show (although I don’t have a reference to hand) is that children declaring a trans status are much more likely to go on to take wrong sex hormones if they are given puberty blockers than if they are not.

Exactly.

Warrior I think this was one of the problems highlighted at GIDS, that there was no record of outcomes/future health. As highlighted by pp, so few children taking puberty blockers do not progress to cross-sex hormones that it might be difficult to draw any statistically meaningful conclusions anyway. Probably there is no peer-reviewed evidence (cos who would fund it 🙄) either supporting or rejecting - except for on-label treatment of course

Understood, thanks.

No. I am pointing out that puberty resumed, but that later many of these women had significant issues that were irreversible. The future health issues, bone density was just one of a long list, were not reversible was my point.

My comment was in regards to Lupron and its effects on female bodies for precocious puberty.

Probably from their proper use, for kids with precocious puberty, it is fully reversible in that when they stop taking them puberty carries on, having been paused.

If you don't have PP then you are preventing normal puberty from happening - and they tend to prescribe them for far longer to "trans kids"

Really don't mean this to sound snippy but why have you put puberty in inverted commas? Is your point that it's not a real puberty?

Confusing thread title - did you mean “reversible”?

The negative side effects for Lupron for precocious puberty tended to occur in adulthood. It is then that the women who had taken it for precocious puberty reported the many issues they had and started to track where it started.

But as far as 'puberty' was concerned, yes, their puberty resumed.

What may not be irreversible is the impact of having stopped hormone production for a period of time.

Yes this is my worry, that bone density for example may never recover.

Irreversible means the opposite of reversible by the way! Two PP have used it interchangeably so far 😁

I suspect that the statement that they are reversible came from the fact that they are (more specifically they will be negated) when stopped for precocious puberty.
As far as I know, the medical industry doesn't make statements relating to off-licence use because anything used in this way hasn't been through clinical trials and approval.
So medics who use this statement to describe off-licence use are either ignorant of that or deliberately using a statement in the wrong context.