count fagula

So, before the advent of cross-sex hormone therapy, one of the surefire ways to ID a biologically female skeleton of a person who had borne children (this is important) was by looking for pits of parturition. These form when the estrogen surge during late pregnancy tells your pelvic ligaments to loosen up in order to fit the baby’s massive head through the birth canal. Your pelvis starts to s There’s hypothetically only one normally occurring biological reason for a body to give that signal, and since you have to be nominally XX (or some variant of that where you can still carry a pregnancy to term), it was a pretty solid shorthand for sex!

Until we started looking for these things outside of female skeletons, and surprise! “Male” skeletons can have them too! Sometimes these are chromosomal variants, sometimes they’re men with a high estrogen or estrogen-esque hormonal component, and in the modern era? Sometimes these are trans women whose skeletons have undergone hormonal changes due to taking estrogen.

And then there’s testosterone. You know what that does, right. It makes it easier to build muscle. But what THAT does is put new and interesting stresses and pressures on the bones, making them more rugged and in line with the skeletal structure we see in people who have had high testosterone their entire lives. We don’t just see this in trans men- we see this in older cis women too. Once your estrogen production tanks after menopause, we see what we call masculinization of the face, where the features get more rugged and robust as tissue production changes. These changes don’t happen overnight, and we don’t have good data (yet) but my guess is that when we start looking at the skeletal remains of trans men who took T throughout their adult lives, their skulls are gonna look pretty damn masculine.

The TL:DR from all of this: there is good evidence for skeletal changes during adult-initiated HRT. We know that these changes occur, but there isn’t a whole lot of literature about exactly what occurs. Many of these changes are minute and you may not see them in a living trans human, but are more discernible in a skeleton. We need to study this more.

Introductory Stuff

A nice Sapiens article proposing how to improve trans visibility within bioarchaeology/forensics: https://www.sapiens.org/biology/transgender-intersex-forensic-anthropology/

Why it’s important to be able to talk about the bodily changes trans people go through as an anthropologist: https://journals.upress.ufl.edu/fa/article/view/1409

Studies of skeletal development in trans people taking hormones

Bone health as a part of trans healthcare: https://www.sciencedirect.com/science/article/pii/S8756328208007722?casa_token=Q0yyPHewOLIAAAAA:f6VKhwq1uVylVHkVZtAX6c-t3WADx8aaymmIWtiUeci1dqVuYAMH9OXn2ofmm4T1thKw5dkutuw

Hormones and bone density: https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1365-2265.1998.00396.x?casa_token=o2l0Y9Nt4qoAAAAA:tO3_aIeM4RqBE0xyNpC8Ns8d7vipYNFzsdMdaX5ZcodO9JShKdEkh-Vw-66FKJAW13bDG2pCCKKUYeyc

Interesting paper on pelvic morphology changes: https://asbmr.onlinelibrary.wiley.com/doi/full/10.1002/jbmr.4262

(this one’s about people who started HRT before 18, but it’s still a really interesting read even if it isn’t directly applicable to OP’s situation since they transitioned as an adult)

10 year bone health study in transgender individuals: https://asbmr.onlinelibrary.wiley.com/doi/full/10.1002/jbmr.3612

Not hormones, but stuff on how FFS affects skeletal remains: https://pubmed.ncbi.nlm.nih.gov/32200173/

Ok, so we’ve identified that there ARE bone changes. How does muscle affect bone structure?

Explains the bone/muscle relationship in typical cis men and typical cis women: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3189615/ (Note: by typical, we mean that their hormones are generally within the range that’s expected for their chromosomal composition.)

Comparing trans men on long-term HRT to cis women of the same age and looking at bone mass, body composition, etc: https://academic.oup.com/jcem/article/97/7/2503/2834495

Facial masculinization of the female cranium with age: https://digital.library.txstate.edu/bitstream/handle/10877/5250/NAPARSTEK-THESIS-2014.pdf?sequence=1

Cranial remodeling with age: https://onlinelibrary.wiley.com/doi/full/10.1111/joa.12247

(The aging stuff is important because hormonal composition changes drastically with age and it’s a useful analogue, if not direct analogy.)

Some interesting reads on the relationship between sex hormones and cartilage

Estrogen and osteoarthritis (aka cartilage loss): https://www.mdpi.com/1422-0067/23/5/2767/htm

More sex hormones and osteoarthritis: https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj.27.1_supplement.1053.15

Generally speaking, HRT isn’t going to do too much to the cartilage. If you think your nose looks different, it’s probably because you’re seeing it in a new context since the fat deposits on your face rearrange themselves. They’re very close to the surface, after all. 

Pelvic Scarring and how it’s not strictly based in pregnancy

Oops we found it in men: https://onlinelibrary.wiley.com/doi/10.1002/oa.2887

It’s also found in women who have never given birth: https://digital.library.txstate.edu/bitstream/handle/10877/8481/GALEA-THESIS-2018.pdf?sequence=1

Identifying transgender people within archaeology

https://miami.pure.elsevier.com/en/publications/the-fallacy-of-the-transgender-skeleton (good read on how human sexual dimorphism... isn’t. The spectrum of traits overlaps too much.)

surgery piece: https://www.sciencedirect.com/science/article/pii/S0379073820300827?casa_token=jy_vbV7_fXkAAAAA:nz2d-xCUT-JoYACam3CDliKmto1UFkB8-ft837QzSpjLZJ0uiH5DHNSH7M_fG_b5XWsln3yZZKk

As for the mechanism, it’s a combination of remodeling and changes in bone density. The bones don’t unfuse, so you’re basically stuck with the same structure, just with different sizes and densities. This is more notable in trans men- they can lose some height from bone density loss if they’re not careful. It’s usually not a lot and isn’t as noticeable in living people as it is in skeletons, because there’s a lot more tissue to you than just bone! It’s the same mechanism that happens in cis women with osteoporosis. Fortunately, most endocrinologists take that into consideration these days.

Right now, most of the research on skeletal changes is focusing on FFS because it’s much more visible and dramatic. There’s a lot of reasons we don’t really understand everything that HRT does to the skeleton- we know a lot of it, but not everything- and how any of it shows up in the archaeological record. One of them is that HRT is relatively new and we don’t have the representation in skeletal collections. Another is that most of our standards are written based on studying white people, and while you can’t truly identify race from a skeleton, you can associate a skeleton with certain genetic groups based on suites of traits. By only including white skeletons in a study, you miss out on a TON of variation.

I've spent the last two months coloring in various pictures of SEAFOAM I took with flipnote 3D on my beach trip. I waded straight out into the ocean with my 3DS and it only got a little wet.

"No." Says the tuna, "Do you?"

"I have never seen it." Says the whale, "but deep in my body, I remember it."

"Why do you care," says the tuna, "if you will never see it."

"There are bones in my body built to walk through the forests and the mountains." Says the whale.

"They will disappear." Says the tuna, "one day, your body will forget the forests and the mountains."

"Maybe I don't want to forget," Says the whale, "The forests were once my home."

"I have seen the forests." Whispers the salmon, almost to itself.

"Tell me what you have seen," says the whale.

"The forests spawned me." Says the salmon. "They sent me to the ocean to grow. When I am fat with the bounty of the ocean, I will bring it home."

"Why would the forests seek the bounty of the oceans?" Asks the whale. "They have bounty of their own."

Last year I finally had an excuse to illustrate this simple little Tumblr story I've had bookmarked forever for class.