When young TIMs take "puberty blockers" followed by exogenous estradiol, they still end up growing to male-typical adult heights - and thus they can expect to go through life standing out as noticeably taller than the female people whose appearance they hope to mimic. This is the finding of a paper accepted for publication last week by The Journal of Clinical Endocrinology & Metabolism titled, "Trans girls grow tall: adult height is unaffected by GnRH analogue and estradiol treatment."

In the paper, clinicians in gender medicine in Amsterdam looked at 161 TIMs who in adolescence took GnRH analogs to block puberty as well as either "estradiol at a regular dose (2 mg) or high growth-reductive doses of estradiol (6 mg) or ethinylestradiol (EE, 100-200 µg)." The latter group were given high dose estradiol specifically for the purpose of stunting their height so they'd more closely resemble females in appearance.

Despite these interventions, both groups ended up having normal adult height for males anyways. This caused the authors of the paper to conclude that adult height is determined more by sex chromosomes and genetics rather than by sex hormones.

Growth and bone maturation decelerate during PS [puberty suppression] and then accelerate again after the start of GAHT [gender affirming hormone treatment, in this case estradiol]. Overall, the regular treatment seems to have little impact on adult height.

This study also gives insight into the regulation of growth and the role of sex hormones versus sex chromosomes. The finding that transgender girls, who have XY chromosomes and are treated with estradiol, reach an adult height close to the population mean for males suggests a minor role for sex hormones. This is in line with findings from studies in subjects with complete androgen insensitivity syndrome (CAIS) or XY complete gonadal dysgenesis in whom adult height was closer to male target height or average height in the male population (40, 41). This supports the idea that genetic factors rather than sex hormones, are important in regulation of growth (41, 42).

https://academic.oup.com/jcem/advance-article/doi/10.1210/clinem/dgac349/6603101?login=false

The more research done in this area, the starker the sex differences become. Yes, both male and female humans go through an important stage of development known as puberty of adolescence, but what happens - and how and why - to the two sexes during puberty are not analogous. They're not even necessarily comparable.

One of the most glaring of all the many problems with "gender medicine" is that it's based on erroneous assumptions, such as the assumption that 1) the only significant physical difference between human males and females is our sex hormones; 2) changing people's sex hormones will cause them all to become visually indistinguishable from the opposite sex; and 3) interventions like "puberty blockers" that work in particular ways and produce certain effects in males will work in the same exact ways and produce similar or comparable effects in females. But when actual research is done, it often proves the opposite.

The evidence I've seen is that when young TIFs are put on GnRH analogues aka "puberty blockers" for gender affirmation in adolescence, it causes them to end up shorter as adults than they otherwise would have become.

Although estrogen is what causes people of both sexes to stop growing in height in adolescence because estrogen causes bone plates to close in males and females alike, it appears that estrogen also fuels the pubertal growth spurt and skeletal bone growth of females to begin with - which probably has to do with the fact that female people have different genetics and different hormone receptors than males do, and so are affected differently by the same hormone.

So despite being put on "puberty blockers" that TRAs constantly say are miracle drugs vitally necessary to prevent young TIPs from going through "the wrong puberty" and acquiring the secondary sex characteristics that will reveal their sex to others, both young TIMs and young TIFs put on "puberty blockers" can expect to end up in adulthood with an unmistakable physical characteristic that's one of the most obvious, noticeable and difficult to hide tells of their biological sex anyways - their height.

Once again, this downside of "gender medicine" has more negative consequences for TIFs than for TIMs. Yes, TIMs put on "puberty blockers" will be tall like other guys, but at least they won't end up so unusually tall that they'll stand head and shoulders above other males males. It seems TIFs, however, often will end up unusually short even compared to other girls and women.

Maybe this unexpected consequence of "puberty blockers" for TIFs should be called "the Strangio effect."

At any rate, it's becoming crystal clear that in myriad ways, the treatments ballyhooed as great advances in the field of "child and adolescent gender medicine" keep causing female TIPs to end up getting the short end of the stick.