Thoracic outlet syndrome & deteriorating verbal fluency: Not on your typical informed consent form

Informed consent: Your Golden Ticket to “affirmative” trans health care.

It’s simple. Go to a gender therapist, tell them how you identify and what medical treatments you intend to pursue. Said therapist refers you to an MD, whose job it is to inform you of what you’re about to embark on, including possible risks, and to obtain your consent. Done.

icath model

And while consent forms do tend to cover (in addition to the provider’s buttocks) the better-known effects and risks of hormone “therapy”–in the case of testosterone, things like elevated cardiac risk, deepened voice, hair growth/loss, and changes to sex drive and mood —there are other physical and neurological problems associated with marinating female brains and bodies in far more T than their biology would normally allow.

Researchers in neuroscience who study hormone effects have uncovered some of these impacts; clinician-researchers who focus on trans people are aware of them. But for some reason, the trans-identified females who’ll possibly bear the brunt aren’t fully informed.  Don’t these clinics owe it to their patients to even mention the ongoing research and clinical discoveries? [Note to readers: If you can supply us with informed consent forms which do mention any of the effects discussed in this post, please do so in the comments.]

On the neurology front, there is a significant and growing body of literature across disciplines showing the deleterious effect of testosterone on language skills. A 2016 brain imaging study found that even 4 weeks of testosterone “therapy” may shrink the zone of language in the brain of FTMs, corroborating multiple, prior studies showing an association of T levels with reduced verbal skills. In 2007, Dutch researchers Gooren and Gitay reviewed clinical data on over 700 FTMs from 1975-2004 and found a similar impact. An earlier 1995 study of testosterone treatment in trans-identified females showed a “deteriorating effect on verbal fluency tasks.”

But hey, you might get a bump in your mental rotation skills.  A 2016 fMRI study (coauthored by Peggy Cohen-Kettenis, one of the members of the Dutch team who pioneered the use of puberty blockers in pre-adolescents), studied “gynephilic” girls (otherwise known as “lesbians”) and found changes in brain regions typically activated during mental rotation tasks after just 10 months  on T.

burke et all 2016 gynephilic FTM

Whatever one’s opinions on the data, isn’t this cross-disciplinary, replicated body of research worth a mention, even as a footnote, on an informed consent form?

Moving on to the skeletal front, we found this recent discussion on the WPATH Facebook page amongst providers caring for post-mastectomy trans-identified females. Asked about tips for dealing with top-surgery induced adhesions and other problems, a primary care provider had this to say about adverse skeletal impacts of T on “estrogen-based” people:

T affects the body by increasing muscle size rather quickly. Often in people who were estrogen based to adulthood, that means a lot of muscle has to fit through a small bony prominences at the shoulder, elbow, and wrist this is often especially apparent. This often leads to things like thoracic outlet syndrome, and carpal tunnel syndrome like experiences.

Anyone who has ever suffered from thoracic outlet syndrome knows that it can be excruciatingly painful, last a long time, and can even be disabling and prevent a person from working;  in the worst cases, it can lead to more complications and a need for surgery.  Even if a trans-identified female doesn’t follow the path of many FTMs to becoming a bulked-up, gym/workout enthusiast, the increased risk is there because of the smaller skeletal structure of human females.


As with so much in trans health care, the wanted and unwanted effects of the “treatment” can lead to a need for more treatment (in the case of TOS or carpal tunnel, from physical therapists, orthopedists, and others).

TOS image

Deteriorating verbal fluency. Big muscles forcing through small bony prominences. What else is lurking in the research literature or clinical experience that hasn’t surfaced in media reports, or in the fine print at informed consent clinics? If you know of other under-reported testosterone impacts on trans-identified females, tell us about them in the comments.

One thing we can be sure of: More and more women are starting on testosterone at younger ages, and next to nothing is known about the long-term impacts.