Episode 47: “So, What’s In Your Pants?” (Genitals, Part II)

Eggplant emoji against trans flag.

Our new episode is available from our Podcast host here: Episode 47

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Selected Reading on Trans History:

  • How Sex Changed: A History of Transsexuality in the United States by Joanne Meyerowitz ***CIS AUTHOR AND PUBLISHED IN 2004 SO PROCEED WITH CAUTION
  • Transgender History by Susan Stryker (2008)
  • Black on Both Sides: A Racial History of Trans Identity by C. Riley Snorton (2017)
  • Lou Sullivan: Daring to Be a Man Among Men by Brice D. Smith (2017)


Charles 0:23
Hello, and welcome to Assigned Scientist at Bachelor’s. I’m Charles and I’m an entomologist.

Tessa 0:27
And I’m Tessa, and I’m an astrobiologist.

Charles 0:30
And today we’re doing the other half of our two part series on genitals in the context of trans people, and specifically, medical transition. Last week, we talked about vaginas, broadly. And this week, we’re talking about what many people would present as the absolute and immutable opposite of a vagina. But because we both have advanced degrees in biology, we know that the situation is more complicated.

Tessa 1:01
Oh, yeah, very simplistic binary.

Charles 1:07
So to begin with, I actually, I wanted to address a couple of things that I thought of while I was editing our previous episode.

Charles 1:14
One is, we talked a little bit about the neovaginal microbiome and how there’s been some amount of controversy on what is actually going on in there. I got curious about it, and I looked it up. And there was actually a systematic review published only a couple of weeks ago from when we’re recording this episode. So I’m going to include that in the show notes. And we might talk about it on a future episode. Who knows.

Charles 1:39
Secondly, we kept talking about different structures being homologous. And I realized that we didn’t actually take a moment to define homology – I think, probably because particularly from my perspective, homology is something I think about every single day of my life, because I’m a systematist.

Charles 1:56
But basically, homology in the context of biology is the idea of similarity based on shared lineage, and specifically based on being functionally the same thing that went down a different pathway. So for instance, the tetrapod arm, like the arm of me, a human, and the arm of a bear and the arm of a bird, are all homologous because the modern form of those traits are variations on the same ancestral trait.

Charles 2:33
And then a slightly different meaning is, homology in terms of body parts that are differentiated sexually. So when we say that the penis is homologous to the clitoris, we mean that, at one point during development, like the development of an individual, there was an undifferentiated structure that then went down one developmental pathway and became a recognizable penis, or went down another recognizable pathway and became a recognizable clitoris. And, as we also noted, there’s not just the one pathway or a second pathway, there are a variety of pathways that can happen during human development, leading to natural, completely naturally occurring, variations in the appearance, the size, the shape, the length, the urethral opening position, in the structures because they’re not just like totally different, unrelated things. They’re the same thing that looks different. Do you think that’s a good explanation?

Tessa 3:45
Yeah, no, I think that’s a really good really succinct explanation of what homology is.

Charles 3:50
Thanks. They gave me a master’s degree in insect systematics so… and so like, the penis and the clitoris are homologous, but like – my genitals are not homologous to a cockroach’s genitals? [pause] Probably, I haven’t researched it, but I don’t think there’s one ur-genital at the beginning of all animal life.

Tessa 4:12
Yeah, I don’t think so either.

Charles 4:14
But wouldn’t that be wild? I also shared it with my best friend who is a med student, and they pointed out that we weren’t wrong necessarily, but we were not exhaustive in our presentation of different variants on like, pathways that can happen particularly chromosomally, genetically, etc, etc. Plus the, like, the, the relationship between specific genes and different hormones are very complicated. This is why nobody should go to med school because they got to learn all that stuff but I think… too complicated for me.

Charles 4:49
I mostly have an acrimonious relationship with the human body. I didn’t ask to be in one of these. Thumbs down.

Charles 5:02
Anyway, so those are the things that I wanted to address before getting into the meat – pun intended – of today’s episode: people who were assigned female at birth who developed, you know, vagina, vulva, probably internal reproductive organs and then undergo medical transition to take care of them.

Charles 5:23
So, beginning with history, what is interesting is, one thing that we noted last time, and we noted in our hormones episode, and we’ll probably say many other times in the future, is that the things that trans people do have mostly been developed first for cis people. So we talked about the origin of vaginoplasty not being in creating a vagina for trans women, but in helping cis women. And so this is also the case with phalloplasty. And in fact, the time elapsed between the origin of the procedure for cis men and its application to trans men is even shorter. So when do you think the first phalloplasty was reported?

Tessa 6:08
I’m gonna guess it was probably in the aftermath of World War Two, maybe World War One. I don’t know how good the microsurgery was back then. And then for trans man, it probably happen maybe five years after.

Charles 6:20
You are shockingly close. The first reported phalloplasty was in 1936, and it was primarily done for soldiers from WWI who had experienced traumatic penis injury. And then the first documented instance of phalloplasty as a gender affirming procedure for a trans man was in the mid 40s.

Charles 6:45
Sir Harold Gillies was the first one credited with performing phalloplasty on a quote unquote FTM individual, it was on a physician called Laurence Michael Dillon, who transitioned in the 1940s. And the documentation officially said that it was a surgical correction for hypospadias, which is a intersex condition, where basically the urethral meatus, ie the opening of the urethra, isn’t at the glanss penis, like the end of the penis, it’s like, usually underneath the penis at some point, and it’s considered an intersex condition, because…

Charles 7:21
I think a lot of people have in their mind that intersex conditions are only things that are like ambiguous genitals or something. And it’s many more things than quote unquote, genital abnormalities, but it’s classed in that area. Because hypospadias, it results because it’s a deviation from the expected embryological developmental pathway, where instead of the urethra going all the way through the developed penis, it ends at some point underneath.

Tessa 7:50
And if I recall correctly, it’s actually a pretty common developmental issue more certainly more common than most people realize.

Charles 7:58
And it can be surgically corrected, but it also doesn’t need to be… the the human body is complicated and weird, and it’s tough to live in and you’re all doing a great job. Every day you get up and you refuse to die is a success.

Charles 8:15
Okay, so Laurence Michael Dillon was the first guy, the first trans guy, rather, to have a documented phalloplasty. So it was literally the first reported incidence 1936, the first application to a trans person 1946 – only a decade between its application to cis people, and then it’s appropriation for trans gender affirming surgery, which is incredible.

Charles 8:42
So the way that phalloplasty started, there was one… let me find it actually, because it’s hilarious. There was one paper that I found called “Phalloplasty: The dream and the reality.” And then they start out their introduction with, quote, “the phallus, symbolic of manhood, has received much less attention than the kidney, liver, the heart or the breast, probably because it is presumed that one can live without a penis. Another possible reason for this could be that the function of this organ appears almost magical, responding as it does to changes in emotion, and environment.” And this…

Tessa 9:22
Fine literature for a medical paper.

Charles 9:26
Honestly, and this is a theme that I saw repeated more often than you’d think in literature on phalloplasty, and surgical treatment of a phallus, in general, have this attitude of like… penises are very important. They’re really important and they’re very cool, which… sure, love that for you.

Charles 9:53
But then this relates to what we’re actually talking about, because the incidence rate for phalloplasty in trans masculine people is pretty low, like very low. And one of the reasons that it has remained so low is often because of the perception that the results of phalloplasty are bad. And I mention this not to give an opinion on the issue, but just to say that the results of phalloplasty in general are, quote unquote bad, because of this very unique and as stated, magical notion of the penis, where there is nothing else on the human body, other than the clitoris, that really is like a penis, because of its particular a appearance – people are very keyed in to the phallic appearance, and very jazzed up about it, because phallic stuff is all over the place.

Charles 10:50
And then also, the erectile tissue is kind of unique, because it is this spongy tissue that like, you can’t harvest it from any other part of the body. It’s kind of just its own thing. So the result of a phalloplasty, for a long time was a visual thing, and to some amount of functional thing because of urethral lengthening, ie lengthening the urethra through the constructed penis, so that you can pee out of it, but not a sexually functional object. Because there is no way yet discovered of recreating that kind of erectile tissue that so distinguishes the penis in many people’s minds.

Charles 11:37
So phalloplasty basically, the way that it has functionally worked for a long time that has, has really worked for basically its whole history is getting a skin graft from somewhere on the body, and rolling it up into a tube, and then attaching it to the pubis. And the way that this has changed over time largely is a result of increasing sophistication in surgical techniques in general and plastic techniques in particular.

Charles 12:09
For instance, more recent phalloplasty has been described with the creation of the glans penis, like a visual and physical distinction between the overall body of the phallus and then the clans at the edge with a defined coronal ridge, as well as differences in the location of donor sites on the body. So there are a couple of main places that large skin grafts are taken. So there’s the difference in the location of where the skin graft is taken, as well as whether the it is a free flap, meaning that it is totally disconnected and then reconstructed into a penis shape. And then attached or if it has a pedicle, which, as far as I can tell, is a maintained physical connection to the blood supply of that area.

Charles 13:03
So it’s… looking into the history of this there has there have been distinctions over time, but the fundamental process of taking skin and making it a tube and reattaching it has basically been the same for the past 86 years. And there is a source that I found that I don’t think is open access, but it has a really good visual representation of a timeline for quote, MCF genital reconstruction, and then a separate timeline for quote, FTM genital reconstruction. And I’m not saying that I can get you a PDF. But if anybody needs a PDF, I might know somebody who has one asabpod@gmail.com.

Charles 13:49
So through the 30s 40s 50s, into the 60s that basically was there. The first pedicled flap phalloplasty technique was introduced in 1972. And then I found references to this, but I could not gain access to the paper itself, but 1973 quote, “Durfee and Rowland, the first to describe surgical penile substitution using the clitoris in FTM transgender patients.”

Charles 14:16
And so here, we’re gonna walk down a little side path. So… bottom growth is basically the phenomenon where, if you were born with a stereotypically quote unquote, female, small clitoris, as well as the rest of the whole vagina, vulva, uterus probably, who knows, if you then go on a high dose of testosterone later on in your life, you will almost certainly experience an enlargement both in length and girth of the clitoral structure, at least what is visible externally.

Charles 14:57
And Tessa you are very open, honest, free with information about your own genitals. And I am not going to follow you down that path. You could say to me, Hey, what’s in your pants? And I would say to you, absolutely nothing, because I live in central Arizona, and I refuse to wear long pants. Checkmate. And then you might say, that’s dodging the question. and I would say to you, sure, but what is the actual answer is between me and God, and whatever relevant surgeon there might be.

Charles 15:27
But I will say that I can tell you from various sources of information in my life, that the result of bottom growth really does hammer home the homology of the structures involved.

Charles 15:42
And so this is just a natural result of going on testosterone… I did try to look because when I was beginning to look into transition resources, people would talk about using DHT, which is dihydrotestosterone, so DHT is basically it is formed from testosterone, there is some suggestion, there was some idea that you could apply DHT cream directly to your genitals, and then it would increase the amount of bottom growth that you have.

Charles 16:14
I remembered this, and I tried looking into it. And as far as I can tell, this is a situation of not how much growth but just when you’ll see it, where you could if you’re going on testosterone, you could theoretically add DHT creme to your regimen and then get bottom growth at an accelerated pace. But it seems like – and there’s been no like, systematic study of this, because of course there hasn’t been – but it seems like however much size you’re going to get in your life is what you’re going to get. And DHT is not going to change how much that is, it’s just going to change when you see it. Because typically people will say that they’ll see maximum growth within like three years of being continuously on a quote, male-typical level of testosterone.

Charles 17:06
So then in the 70s, apparently these two guys Durfee and Rowland noticed that this was happening and then suggested, hey, could this be an alternative form of phallus construction for trans masculine individuals. And then it was not until the late 1980s that another publication came out of somebody describing a process for this. And then there are a couple of publications from the 1990s describing this being done in transmasculine patients.

Charles 17:34
Phalloplasty is the total de novo construction of a phallus out of skin grafts from the thigh, from the forearm, from the back from the abdomen, whereas metoidioplasty, otherwise known as meta, is the taking of what God and/or genetics gave you with the help of exogenous testosterone, and using what’s there to create functionally a micropenis.

Charles 18:04
So I think another important point here is, I think some people might think of going on testosterone, particularly, as going on steroids, like super masculinizing your body but the reality is that we are all subjected to the vicissitudes of fate, and by the vicissitudes of fate, I mean your genetic inheritance, where even if you go on a super high dose of testosterone, that’s actually not even recommended, because as you, Tessa, pointed out last time, we all have something called aromatase where if your T levels are high enough, it just becomes estrogen again.

Charles 18:43
So basically then in the 90s metoidioplasty was added and since then the numbers of people who get phalloplasty or who get metoidioplasty are about equal based on the statistics that we have. But the major changes that have happened since then have been in the refinement of technique versus major like new techniques overall.

Charles 19:10
[interstial] So here we are in 2022, and getting a little bit more into detail about the actual like procedures that are used for these different things. First of all, I will say that for trans masc people, it is hard to find information on whether you HAVE to have a hysterectomy, vaginectomy, etc before getting genital reconstruction. I think this is another case of people, having cis people, who are gatekeeping procedures having very clear ideas of what the right thing to do is and therefore requiring that before they will let you have access to something else.

Charles 19:50
So medically I don’t think you need to undergo hysterectomy, vaginectomy, removal of fallopian tubes and ovaries. etc, to then have genital reconstruction – like I don’t think that is a medical necessity – but for many surgeons, it is a procedural necessity. And I think for a lot of people also they’ll just want to get rid of it because they’re like, You’re not welcome here on the premises. And I’m evicting you.

Charles 20:16
Modern techniques for constructing a neophallus, quote, unquote, are divided into metoidioplasty, pedicled flap phalloplasty and free flap phalloplasty. And all of these can be accompanied by scrotoplasty, where, again, as we were talking about last week, in the penile inversion technique, the scrotum are usually used to create labia and then in scrotoplasty, the labia are used as the skin to put scrotal implants in.

Charles 20:47
The testicular implants are not functional implants, they’re not actual organs, they’re just like, silicone orbs. There’s at least one plastic surgeon that I follow on TikTok who talks about this sometimes, and they’re, they’re just testicle shaped balls of silicon. So if that’s important to you, that’s an option. But if it’s not important to you, it’s… there’s no functional reason to have them really, other than…

Tessa 21:08
Yeah, it’s purely aesthetic, yeah.

Charles 21:10
It’s purely aesthetic and mental, and I guess if you’re really into scrotum stuff… I, I don’t know, you do you.

Charles 21:19
So the basic procedure of metodioplasty is, you take the bottom growth that is already there, and it becomes more visibly penile because there are a couple of differences… because the origin point of the clitoris on people who don’t have a penis, or who didn’t have a penis, is a little bit lower on the pubis than the origin point of what is commonly recognized as just like a normal penis, it’s in a different position, relatively and it is smaller, obviously.

Charles 21:57
And so the point of a metodioplasty is not to create a phallus large enough for insertion because with almost everybody, there’s just not enough there, there to do that. But the clitoris is kind of held in the position that it is by several ligaments, like in the pubic area, and so the metoidioplasty functionally just cuts those ligaments, freeing up the clitoris that is there, the clitorophallus rather, so that it can be more prominent and sort of stick out more and be more visible and be a little bit higher up.

Charles 22:29
And then this is often accompanied by using available skin in the area to sort of wrap around to create more girth, as well as urethral lengthening where the urethra is taken from its original position, and then like buccal, mucosa, or a few other options, are used to create an elongated urethra, that is then rerouted from its original position opening below the clitorophallus, and then instead going through it so that the results of metoidioplasty are, a more prominent phallus as well as urethral lengthening to facilitate peeing while standing up.

Charles 23:09
So depending on your surgeon, and your bottom growth already, a lot of people get meta and it basically what you’re getting is that you go from an average length accomplished by exogenous testosterone, and I did write this down… somebody, there was one study that I found that measured, the average length achieved just by natural growth by being on testosterone. And it was, “preoperative length of the hypertrophied clitoris” – which, come on – “can range from 2.5 centimeters” – so about an inch – “to four centimeters with a mean of 3.3 centimeters.”

Charles 23:49
So the average amount of growth overall, that people get, at least from this study, and also from anecdotal evidence, is about inch and a half, maybe two inches. There are some people who get a really incredible amount of growth, but they are not the average.

Charles 24:08
And I think… taking a moment to be emotional, me to the audience, and also slightly humorous, I hope… you would think that if any men in the world would be free from the mental burden of small penis shame and size envy, it might be men who don’t have a penis in the traditional sense. But I’m here to let everybody else know that it is just a universal condition of manhood, that whatever you’ve got, you’re probably going to feel weird about how small it might be. And that’s the real point of connection between trans and cis men. This is what we can all relate on, which is a pretty negative point of connection…

Tessa 24:57
But it is a point of connection.

Charles 24:59
It is a point of connection. Honestly, I would call metoidioplasty more of the true spiritual cousin to vaginoplasty as a practice now rather than phalloplasty, by which I mean, both procedures are kind of taking what’s already there and saying, We can work with this.

Charles 25:17
And from one article that I read called “The role of androgens in clitorophallus development and possible applications to transgender patients,” they specifically noted quote, “The embryologic endpoint of the genital tubercle is the clitorophallus which contains several homologous structures, regardless of developmental pathway. The corporeal bodies are a fusion of the keuro which are attached approximately to the inferior pubic remai they contain blah, blah, blah, blah, blah. All clitorophalli also contain a glans where the initial formation is androgen independent along the shaft of the clitorophallus are nerve bundles which are run along the corporeal body is the densest of which are just lateral to the midline, dorsal [mumbles] whatever.” Right?

Charles 25:56
So specifically, what is being made use of is that homology where testosterone has the effect of enlarging during sort of a pubescent stage, and then the metoidioplasty surgery is using that, and going, great, we can just make this even more apparently typical of like what you would expect from a cis man’s phallus. Now, does it create something that is literally identical? No. But bodies are weird, and we’ve all got different stuff. And that’s the real lesson.

Charles 26:30
And so as noted, the other primary option other than metoidioplasty is phalloplasty, which is just construction of a phallus. The origins of this were to serve cis men who had experienced traumatic penile injury, traumatic both in the sense of losing a lot, and in the emotional sense of, they probably felt pretty bad about it, which is why they wanted the phalloplasty.

Charles 27:02
And so the construction basically is taking a large donor graft from somewhere on the body and rolling it up in a tube. And then a couple of decades ago, someone developed another procedure of tube within a tube, where you have a tube to be the urethra, and then you have a tube around that to be the pole of the penis, and then you would just stitch that sucker on. And there you go.

Charles 27:30
And the thing about phalloplasty is, as noted before, the penis, the naturally occurring penis is a very particular organ that is hard to copy. And so the result of phalloplasty is often perceived as bad, quote, unquote… it’s sort of common knowledge among trans mascs, and then like transmasc community, is that phalloplasty is bad, which I think is very negative.

Charles 27:57
First of all, lots of people have them, so you’re probably gonna make them feel bad about their bodies still. And then secondarily, it depends on what you’re trying to get out of it. Because if you want something that looks like a penis, that you can use to pee standing up, and willhelp you be more stealth in male environments? You got it baby.

Charles 28:17
But if you want, if your primary concern is like sexual performance, the metoidioplasty i is probably going to rank as better because you’re not cutting anything away from the body, you’re preserving what is already there, and just making it more prominent. So there’s like a natural continuation of what it was already doing. Versus if your main concerns are…. even other sexual concerns, where metoidioplasty generally doesn’t produce something large enough for penetrative sex, and a phalloplasty does, then phalloplasty is your better option.

Charles 28:51
And so, you know, especially with increasing sophistication in surgical techniques, I think it’s a very outdated, and kind of thoughtless and even cruel, attitude to say that the result of phalloplasty is going to be bad, and that they’re ugly, and they look weird, like even if you think that… respectfully, keep it to yourself.

Charles 29:10
But I will say that the incidence of problems, like the development of medical problems are much much higher with phalloplasty then with metoidioplasty but specifically, they are mostly related to urethroplasty and urethral lengthening i.e. the urethra is also a very particular thing that is nowhere else in the body and you use it all the time and it’s very important.

Charles 29:39
So the major problems from phalloplasty are related to urethral stuff, but I you know, your mileage may vary. Oh, here’s the quote that I had, “in a relatively recent publication, Betucci et al. presented the results of 85 female to male transsexuals who underwent a phalloplasty using a tubal super pubic abdominal flap incorporating the new urethra made from a medical tube of labile skin.” Basically meaning that there was a super pubic abdominal flap, ie donor skin from the abdomen of the pubis, incorporating the neourethra made from a pedicle tube of labile skin. So they took labile skin, they made it into a urethral tube, and they used a pedicle so that it was still attached that they were able to “create a penis with good cosmetic appearance and almost two thirds of their patients but the complication rates were significantly high 70%. As most of the complications with these slabs are really related to urethroplasty. Many surgeons have attempted to perform phalloplasty in urethroplasty using an abdominal skin flap, and a bladder/buccal mucosa graft. Although complications are common with this techniques, it creates a phallus of reasonable size and shape.”

Charles 30:46
And this is not particularly untypical of results overall, most complications that I could find related to phalloplasty were related to urethroplasty. And the lengthening of the urethra, I think, because you are having to use these kind of makeshift solutions because much like the erectile tissue that distinguishes the penis, from other parts of the body, the urethra is a particular structure in a particular place. And if you are constructing a longer one, you’re going to have to use skin tissue that was not originally meant for that purpose. And because of the particular function of the urethra in shuttling urine out of the body, it’s very important and pretty sensitive.

Charles 31:27
But you know, the satisfaction rate with both forms of surgery and with vaginal plasti are all pretty high, like overall very high. And a lot of the regret that we see discussed like this, this spectre of regret haunting people all the time when they talk about surgery in general and genital surgery in particular, is this like, well, it’s going to be bad. It’s not going to work. It’s not going to be satisfying.

Charles 31:55
But I think the incidence is so low that usually the people who get genital reconstruction surgery are people who really, really want it. And in those cases, the results that they can get, even if they aren’t what people who don’t want them would consider perfect or even good, they are good enough that they satisfy the desire that people had for surgery. Do you think that makes sense, like is that?

Tessa 32:19
Yeah, yeah.

Charles 32:21
And a final thing that I wanted to note is that, in one thing that I read, an article called “Is clitoral release another term for metoidioplasty?: A systematic review and meta analysis of metoidioplasty surgical technique and outcomes,” which I will link in the show notes and which just discusses sort of four major sub categories of metoidioplasty based on specific minor changes in technique they noted quote, “surgeons have also begun to offer a less conventional gender affirmation such as zero depth vaginoplasty and clitoral release without urethral lengthening.”

Charles 32:54
And I think this is another important thing to note in conversations of regret, where I haven’t seen a systematic study of this, because a lot of the time, if you are looking for answers on a question about transness, and medical transition, you’re not going to find them, because people haven’t bothered to systematically study them – but I think incidents of regret, a large part of that comes from lack of flexibility in surgical options or in medical transition options overall, where…

Charles 33:26
In the past, if you wanted to be on hormones, you would often have to have severe genital dysphoria or you weren’t considered a quote unquote, real transsexual, and thus couldn’t get access to anything. So a lot of people got genital surgeries that they didn’t really want, because they did want, very badly, hormones, and the only way that they could get a prescription was to also agree to general surgery. Whereas now not only is that not required – where the sort of the de facto option is to go on hormone replacement therapy, and maybe have surgery – but not only is that an option, but there is increased flexibility in the actual options for genital surgery that are offered, which I think will drive the regret rate yet lower, where it’s already extremely low, you know, I mean, right?

Tessa 34:15
Right. You know, and again, we’ve talked about that before and previous episodes, or when we were talking with Lee about you know, that ironically, having this sort of gatekeeping can increase the rate of regret.

Charles 34:26
Yeah, I think it comes back to a difference in attitude of, a lot of gender critical people and just straight up conservative trans haters have this idea of this like, essential sacrality of the body. Where, doing something outside of the range of what they perceive as normal bodies is like either an affront to nature or an affront to God. And sometimes both, you know, sometimes we can get both within one day.

Charles 35:00
Whereas I have the attitude, and I believe you have the attitude and many other trans activists and just trans people have the attitude of, bodily autonomy being the ultimate value. Oh, people should be allowed to modify their bodies in ways that may be unconventional, but bring them satisfaction and comfort. And I think that’s the major sort of conflict that has gone on where historically, the gatekeeping around trans people around access to medical transition and gender affirming care has been, how do we make these transsexuals appear as normal as possible? We can’t just have people running around with heavily masculinized bodies and a vagina! That’s weird.

Charles 35:51
Whereas now we would say, that’s nonsense. We’re all gonna die someday. The world is on fire. Let’s have a party. You know what I mean? Let’s all just be chill about it.

Charles 36:08
So for the final part of this episode, I wanted to take a look into the future. And particularly Tessa, what would you say in terms of things that we don’t have, but we might have, like things that seem within the realm of possibility that you would want transition wise?

Tessa 36:32
I know just speaking for myself, and I think I mentioned this before, if someone creates some sort of like, I don’t know synthetic ovary, like endogenous hormone production, something or other, I don’t know how you do it, presumably, a fair amount of tissue engineering would be involved or just really good process medical prosthetics, but that would be ideal.

Charles 36:54
I’m right there with you. The number one thing that I would like, is if basically, a genetic switch could be flipped in the gonads that I already have just that I wouldn’t need to add exogenous testosterone into my system.

Tessa 37:10
Yeah, exactly.

Charles 37:11
So I wanted to do a little bit of research on sort of two things that we’ve talked about before. First, the idea of like, reciprocal transplantation, where we have a bunch of people who have certain organs who don’t want them, and in fact, want a different set of organs. And then we have a whole other group of people who are experiencing the same thing in reverse, just pair people up, get, you know, one person’s reproductive system out of there, put it in the other person, get theirs out of there, put it on the other person, you’re gravy, right?

Charles 37:48
Unfortunately, this is not at present a possibility. But I did look specifically at examples of whether we have had successful penile transplants and uterine transplants. And the thing is, yes, we have. So beginning with penile transplants, the first attempt was in 2006 in China. And it was successful in that they got it onto somebody’s body, but there was an ex plantation – they took a back off shortly thereafter, I think because of some psychological problems that were happening, which, fair enough.

Tessa 38:29
Apparently, that happens with that sort of transplant, because I know like the first person to get a hand transplant later requested that it be removed.

Charles 38:39
Yeah, I mean, if we refer back to our good friends who wrote “Phalloplasty: the dream and the reality,” you know, the penis is a very personal organ. And getting somebody else’s randomly, I think would be a pretty big shock. So I understand, insofar as I can understand, having never had anything transplanted to my body.

Charles 39:01
But there have been multiple successful penile transplants since then, mostly in the past decade. So there was one in 2014, one in either 2015 or 2016 – different sources say different things – and then another one in 2018, and the one in 2018 was the most extensive where previously it had been just the penis by itself, whereas the guy in 2018 got a whole chunk of tissue from a recently deceased donor that included part of the abdomen, scrotum and the penis, and they did remove the testicle from the scrotum for bioethical concerns, given that if you had somebody else’s testicle, you could be producing sperm genetically identical to the deceased donor. And that’s a whole can of worms.

Charles 39:59
I think that’s… basically the extent of it. I did search specifically if anybody had attempted penile transplants onto a trans masculine individual, and I saw a flurry of articles from around 2020 saying that somebody was planning to attempt it, but I haven’t seen anything since then suggesting that they actually have. But theoretically, I can’t see any reason why a successful transplant couldn’t occur on somebody who never had one versus somebody who already had them.

Charles 40:37
Because there’s… maybe something there, where the original phalloplasties were not completely de novo the whole situation, they were largely done on people who had like, penile stumps left over. So there was still they were building on to a base what was already present.

Tessa 40:56

Charles 40:56
And then similarly, you could think maybe the original penile transplants, there was some original tissue, like the cavernosum tissue left over, like the erectile tissue of the penis, so they had supplementary materials, I guess, from the recipient, but with the guy from 2018, it was like lifting a bunch of stuff – like 10 inches by 11 inches – from the donor body and transplanting it onto that guy. And from what I read, there was demonstration of urinary success so that he could urinate through it and no information on like erectile success. But I mean, fingers crossed for that guy.

Tessa 41:37
We’re rooting for you, guy, wherever you are.

Charles 41:39
We’re rooting for you. I mean, he did talk about in the articles that I read… obviously, the reason why genital reconstruction surgery is so important to trans people, is that genitals are important to most people, right? Like, they are a part of your self and your body and having any kind of quote unquote, abnormality, whether it’s congenital, or acquired, or socially defined… it’s a very sensitive thing for people and it can make you really lonely and make can make you feel like you can’t get into relationships. And so for, you know, genuinely from the bottom of my heart, I’m rooting for that guy. So that’s penis transplants.

Charles 42:19
And then I also looked into uterus transplants and the thing is, uterus transplants have been much more frequently done, and much more demonstration of success where from one article that I found, quote, “currently, more than 70 uterine transplants have been performed worldwide, resulting in more than 23 live births” – from a source from 2019. So that’s pretty incredible.

Charles 42:46
And this has been done both from deceased donors, so people who died and then the uterus was taken out, and from live altruistic donors. Another source that I found, quote, “additionally, a team from the Czech Republic demonstrated that uteri from nulliparous deceased donors can result in successful live births.” So both living and dead donors have resulted in, one, successful transplantations where they weren’t rejected by the recipient, and successful use of that uterus, to result in a live birth. And so that I think, is great news.

Charles 43:22
As far as I can tell, this has been demonstrated only in cis women who either have lost their uterus from hysterectomy or who were born without a uterus, but it has not been demonstrated in any trans feminine people or otherwise assigned male at birth people who just not only didn’t have a uterus when they were born, but nobody expected them to have a uterus based on their other physical characteristics. However, multiple sources that I found, different doctors, suggested that the limiting factor here is not the possibility of transplanting but the likelihood that people would throw a real fit about it.

Tessa 43:59

Charles 44:00
Which we, I mean, if maybe Tessa you can potentially fill in any uninformed people in the audience that gender criticals, terfs, transphobes are already losing their minds about the possibility of trans women.

Tessa 44:14
Oh, yeah, yeah. Yeah. Like there are people admittedly, these are also people who think friends, people use this thing as part of some sort of nefarious conspiracy to like, have us all upload our brains into the machine or something. But yeah, there are people who are convinced that any day now trans women are going to come and start literally stealing ces women’s uterine, you know, like in, you know, Repo!, but without Paris Hilton, and somehow even less intelligent.

Charles 44:40
[softly ] God… [normal voulume] Repo! was not a movie. But, one article that I read specifically was like, well, listen, we got transfeminine people who would like a uterus, and we got transmasculine people who are trying to evict that thing from the premises. Why don’t we pair these guys up? And so… this actually made me feel really happy. The inclusion… a) the inclusion of it at all, but then also quote, “of 31 TGM respondents 96.7% had positive attitudes initially. And 84% wanted to volunteer for uterus donation after hearing detailed procedural information,” which just warms my heart. It makes me feel really good about us. That we’re like, yeah, man. I don’t want it.

Tessa 45:25
Yeah. Y’all guys are doing good.

Charles 45:28
It just made me so happy. And anecdotally, like, I, yeah, I would do it. Whatever. I don’t want it, sure. I am actually interested, Tessa, because I think you, you said in a previous episode that you had signed up for, like on the list of people who would be willing to be part of like an experimental process of transplanting a uterus into a transfer? Is that because you are excited about science and being an experimental subject, or is that a reflection of like, if given the opportunity, I would like to gestate and birth the child?

Tessa 46:03
Yes, to both cases, but most of the former, since I am not in a position to actually have a child right now, like financially or anything like that. Mostly, it would be for the sake of science?

Charles 46:14
Well, here’s a related question, if you were part of that kind of a study, and they were like, we are specifically looking for people who would be willing to experience some form of pregnancy like, would that would that expectation affect your willingness to participate?

Tessa 46:30
Yeah, potentially, because I feel like I… it would be more ethical for me to not take that space or slot because I’m assuming that we live in a world of scarcity. So you know, there’s gonna be a limited number of procedures available to someone who actually does intend to, like actually bear a child.

Charles 46:46
Yeah. And so they also mentioned the possibility of androgenic effects hurting uteruses? Because obviously, if you are a cis woman who has a uterus and you volunteered to donate it to somebody, probably that uterus has been in the body with quote, unquote, female typical levels of estrogen and testosterone versus if you are a trans masculine person who has been on testosterone for a long time.

Charles 47:13
Would that then… because we know that testosterone can cause like, vaginal atrophy, so would that affect the quality and the functionality of the uterus, and their suggestion is, quote, “the impact of androgens on endometrial function is not permanent. And endometrial function should normalize following cessation of the androgens” – as long as you are on testosterone, your uterus is going to be a little bit weird, but as soon as you go off of testosterone and then go back on to a higher level of estrogen relatively then function can resume.

Charles 47:47
That’s borne out in what we’ve seen of, trans masculine people who are on testosterone for a long time, they go off of testosterone, they get pregnant, they give birth to a bab, go back onto testosterone, and they are able to go through that process. So the organ is fine.

Charles 48:05
Presumably, I think penile transplants are… and I’m not a doctor, or a futurist, or anybody other than some random guy who loves insects and cats, right? But my guess from what I can tell is that genital transplants are probably pretty far away, if they are likely to come to us at all. Uterine transplants… probably also still pretty far away. But we have seen repeatedly that uterine transplants can happen successfully, and produce children afterwards. So I don’t think that it’s an impossibility, although there are some remaining problems brought up for instance, whether a neovagina could serve as a birth canal as…

Tessa 48:55
Yeah, my understanding has been in those situations any child conceived and born would probably be born through C-section.

Charles 49:04
Yes. And I also saw in at least one article talking about how the uterine transplants were not permanent, they were like removed afterwards.

Tessa 49:13
Yeah, they take them out, autoimmunity concern, yeah.

Charles 49:17
Well, cause, exactly… and that’s the other issue that I saw brought up again and again, of like, if you transplant something, then, you know, the person who got the transplanted thing has to go on, like, immunity suppressing drugs forever. And that’s obviously justifiable if you are transplanting a life-sustaining organ that you literally cannot live without, but is perhaps less justifiable, for instance, for a penile transplant, especially given that phalloplasty is a technique that we have.

Charles 49:52
So honestly, I’m interested in your perspective here where if we lived in a world where you could have a van transplant, but then you would have to act as people do after they have transplanted organs versus the results gotten by available vaginoplasty techniques. What would your preference for that be?

Tessa 50:16
I mean, I have to admit, I’m pretty happy with the results I have now. And I don’t know if I’d be willing to, like, take immunosuppressants for the rest of my life.

Charles 50:24
I feel like part of the deciding factor in these cases in the hypothetical where, you know, they’re all kind of equally possible and available, would be whether you are deeply affected by the kind of dysphoria of, feeling like something is essentially not identical to a cis version, like the kind of dysphoria that digs deep within and makes you feel like well, but my chromosomes though, do you know what I mean?

Tessa 50:54
Yeah, yeah, I have to admit, that is not something I normally experience, though. I know, I do know of trans people who do. But in my case, generally speaking, whatever part of my brain is responsible for dysphoria only really cares about what is like, immediately physically tangible to me.

Charles 51:11
I think. I think I’m… yeah, I mean, to be honest with you, at this point in my life, my major remaining source of dysphoria is just the size of my hands, because they’re pretty small. But on the other hand, more nimble fingers are good for handling insects. So God giveth and God taketh away, you know what I mean.

Charles 51:37
So I looked at that, and then I also looked at whether it would be possible to do switching gonads from primarily producing estrogen to primarily producing testosterone or the other way around, and they have done it… in mice. There was one paper published in 2009 that got reported on a lot… from Cell in 2009, quote, “Somatic Sex Reprogramming of Adult Ovaries to Testes by FOXL2 Ablation.” So essentially, they ablated FoxL2, which is a gene that produces this transcriptional regulator, FOXL2, where… Tessa, why don’t you tell the people what a transcriptional regulator is?

Tessa 52:23
So basically, it controls when and how a gene gets transcribed to in turn produce a protein or enzyme or other biological compounds that your body uses

Charles 52:35
Beautiful. They basically turned that off, which then led to upregulation of genes, including Sox9. And so Sox9 is one of the genes that we did not talk about in our episode last week talking about like the embryological pathway of sexual differentiation, but it is implicated in part of that, where the SRY gene is important to kind of get the ball rolling, but then there are other genetic triggers, there are essentially a series of like gateway checks and latches – metaphorical latches – of ways to keep things going the way that they’re going. And it’s not just the SRY gene, and then you’re done.

Charles 53:22
So from that article, quote, “here we show that upon conditional loss of FoxL2 in the adult ovary, the two major female specific somatic cell lineages, switch their cell fate revealing a rare example of true adult lineage reprogramming in vivo,” continuing, “while granulosa cells, which support oocytes, are reprogrammed into testis specific sertoli-like cells, the steroidogenic theca cell lineage upregulates 17, beta hydroxysteroid dehydrogenase type three, the rate limiting enzyme of testosterone biosynthesis resulting in male like levels of testosterone in the blood.”

Charles 53:58
They created conditional loss of FoxL2, which then resulted in Sox9 being upregulated – Sox9 being another gene – resulting in the reprogramming of these ovary cells into sertoli-like cells, Sertoli cells being the type of cell that is responsible for androgenizing in the fetal testes and then continues to be present in testicular tissue to produce testosterone.

Charles 54:27
And so basically, what they did is by switching off one gene, they were able to prevent the ovary from continuing to tell itself, “we are an ovary, we’re doing ovary stuff,” and then it started producing testicular cells, and androgenizing, which is pretty cool. Unfortunately, this is in mice, and you’ll notice that a mouse is not a man.

Charles 54:51
Also quote, “FoxL2 and Sox9 oppose each other’s actions to ensure together the establishment and maintenance of the different female and male supporting cell types, respectively.” The idea being that, if FoxL2 is activated, you continue along the female quote unquote, pathway, and if Sox9 is activated, then you go along the quote unquote, male pathway. And they are in opposition to each other. Where the actions depending on gene regulation, you have one or the other. And they do essentially, in the hormone binary that we’ve constructed of estrogen and testosterone, they do opposite things.

Charles 55:28
And so then you might ask, Well, if this can happen to ovary tissue, can this happen to testicular tissue? And the answer I would give you is yes. So in a later publication from 2016, quote, “here we show that after ablation of socks nine in sertoli, cells have adult fertile socks, eight negative mice testis to ovary genetic reprogramming occurs, and sertoli cells trans differentiate into granulosa-like cells.”

Tessa 55:56

Charles 55:56
Yeah, I don’t think this publication mentioned this resulting in increasing levels of estrogen production in those mice. There are a couple of things here, one, I could have missed it. I’m busy, too. It’s possible kind of the same thing that we talked about in our hormones episode, where we typically think of high levels of testosterone, basically nullify present estrogen versus high levels of estrogen do not in the same way or at the same levels lower testosterone levels, but as we also talked about in the hormones episode, that could also be wrong information. So very interesting. I did actually see one post on Reddit of a trans girl like, I would like to get an orchiectomy, but I’m worried that this might become a possibility.

Tessa 56:51
Yeah, I can understand that. Like, because I was just thinking, Well, I’m out of luck, but that’s sure still sounds cool.

Charles 56:56
Yeah. The good news is you may yet die before this is a reality for adults.

Tessa 57:01
[unsurely] Thanks?

Charles 57:03
Good news, bad news. [laughs]

Charles 57:10
So if you want to find me online, I am on Twitter @cockroacharles and I realized the other day that people may not know what I’m actually saying. It’s the word cockroach, and then a-r-l-e-s, like the rest of my name, because cockroach ends in -ch and Charles begins with -ch, and that’s where I am

Tessa 57:34
And I am on Twitter @spacermase, or on my website at tessafisher.com.

Charles 57:41
The show is on Twitter @ASABpod or at our website where we post show notes and transcripts for every episode asabpodcast.com. If you like the podcast, and if you think other people might like the podcast or benefit from any of our episodes, please tell people about it because that’s the number one way that podcasts grow.

Tessa 57:59
And until next time, keep on science-ing.

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