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[–]Cass 7 insightful - 1 fun7 insightful - 0 fun8 insightful - 1 fun -  (1 child)

Seems like this person says you need gender dysphoria to be trans, which goes against the latest amendments to the gender constitution.

[–]Kai_Decadence[S] 3 insightful - 1 fun3 insightful - 0 fun4 insightful - 1 fun -  (0 children)

Yeah it appears so since they claim to be a med student and are trying to come from a scientific angle but it leads to the question of "what is gender dysphoria?"

[–]MarkTwainiac 6 insightful - 1 fun6 insightful - 0 fun7 insightful - 1 fun -  (2 children)

It occurs in prenatal development when the nervous system starts to develop - it can be affected by raised hormones in the mother's blood (testosteron for XX ferus and estrogene for XY fetus) and the brain will start developing as it should for opposite sex. (also the neuronal connection for your "gender" will be performed - idk how to describe it better in english im not native english speaker sorry).

This is hogwash. The med student who wrote the passages you quoted seems to think that during gestation in utero pregnant women pump out sex hormones willy-nilly that then pass directly to the embryo/fetus unmediated. This isn't the case.

The extent to which the mix and levels of hormones made by pregnant women's gonads and glands get into a developing embryo or fetus and match up to the hormones inside an embryo/fetus is unclear. For obvious reasons, getting samples of human embryonic or fetal blood is so risky that it's unethical and just not done, so there is much that science and medicine don't know about the relationship of maternal and fetal hormones in humans.

But the sex hormones that most heavily influence the development of human fetuses appear to be those made by each fetus's own internal organs - mainly the fetal gonads, which are either testes or ovaries, and develop at 7-8 weeks post-fertilization, and the fetal adrenal glands. If anything, it appears that the hormones a fetus makes from its own gonads and adrenals have at least as much - or even more influence - on the mother's hormones than the hormones made by the mother's own ovaries and glands have on the fetus.

Yes, of course a human fetus is exposed to circulating maternal hormones to some extent. But it's not like whatever hormones the mother's ovaries, adrenals and fat cells pump go directly into a developing fetus. This is because of the role of the placenta, the special endocrine organ grown during pregnancy that connects the circulatory systems of the mother and the embryo/fetus and serves as a protective interface between the two.

The placenta does many different things to insure that an embryo/fetus won't be harmed by things the mother ingests or is exposed to that get into her blood.

One role of the placenta is to prevent the mother's immune system from responding to the offspring she is gestating as though it didn't belong the way transplant recipients customarily mount rejection responses to transplanted organs. BTW, a sex hormone seems to play the most important role in suppressing the maternal immunologic response to fetal antigens - but that sex hormone is neither testosterone or estrogen; rather, it's progesterone.

Another role of the placenta is to protect female fetuses from exposure to maternal testosterone. A fact few genderists seem aware of is that pregnant women don't just have naturally elevated levels of estrogen, they have have naturally elevated testosterone. The normal range for women age 18 and up is 0.02-1.68 nmol/L. Pregnancy range is 1.7-4.2 nmol/L. When a woman is pregnant with female offspring, the placenta converts the high levels of the natural T in the mother's blood into estrogen through the process of aromatization.

During fetal development, aromatase converts androgens to estrogens in the placenta, which is the link between the mother's blood supply and the fetus. This conversion in the placenta prevents androgens from directing sexual development in female fetuses. After birth, the conversion of androgens to estrogens takes place in multiple tissues.

In the extremely rare event that there is an aromatase deficiency in the placenta, a female fetus will become androgenized. Aromatase deficiency used to be considered a disorder incompatible with life, but a few cases of the deficiency have been reported in children and adolescents. However, aromatase deficiency in females leads to a disorder of sex development in which the sex organs are visibly affected. The med student who wrote the passages you quoted seems to think that the excess testosterone could and would affect a female fetus's developing brain and nervous system without affecting the development of the genitals. But this isn't the case.

The role of the placenta in regulating the hormones a male fetus will get from the mother is less clear. However, studies of women babies in parts of the world with very high pollution and environmental toxins suggests the human placenta is capable of protecting male fetuses from exposure to harmful environmental chemicals and hormone disruptors that mimic estrogens and could interfere with normal male development, such as Bisphenol A.

The med school student who wrote the passages also makes the error of thinking that the development and functioning of brains in males in utero and later on in life are entirely dependent on testosterone. But that's not the case.

Male behaviors require both testosterone and estrogen. Circulating testosterone activates the androgen receptor (AR) and is also converted into estrogen in the brain via aromatase. This conversion is the primary source of estrogen to the male brain. It is unclear whether testosterone and estrogen signaling interact to masculinize neural circuits. Using a genetic approach, we show extensive sexual dimorphism in the number and projections of aromatase expressing neurons. The masculinization of these cells is independent of AR but can be induced by either testosterone or estrogen, indicating a role for aromatase in sexual differentiation of these neurons.

Testosterone is required for male behaviors in most vertebrates, including mice and humans. Testosterone mediates its effects by activating AR and male mice mutant for this receptor do not display sexual behavior or aggression (Ohno et al., 1974). Testosterone is essential in newborn and adult male mice for the display of sex specific behaviors such as aggression (Finney and Erpino, 1976; Peters et al., 1972; Wallis and Luttge, 1975). This testicular hormone is thought to masculinize neural circuits in neonatal rodents, and to act upon these pathways in adult males to permit the display of dimorphic behaviors (Phoenix et al., 1959).

Estrogen is also essential for male behaviors. The requirement for estrogen to masculinize behavior seems counter-intuitive as this ovarian hormone is essentially undetectable in the male circulation. All estrogenic steroids are synthesized in vivo from testosterone or related androgens in a reaction catalyzed by aromatase. Aromatase expressing cells in the brain convert circulating testosterone into estrogen, and it is this local estrogen that is thought to control dimorphic behaviors in males (Figure 1A) (MacLusky and Naftolin, 1981; Naftolin and Ryan, 1975). Consistent with a requirement for estrogen in male behaviors, aromatase activity is essential for male behaviors. Mice mutant for aromatase exhibit a profound reduction in male sexual behavior and aggression (Honda et al., 1998; Toda et al., 2001). Similar to testosterone, estrogen is essential in neonates and adults for the display of dimorphic behaviors in males (Finney and Erpino, 1976; McCarthy, 2008; Scordalakes and Rissman, 2004; Toda et al., 2001; Wallis and Luttge, 1975). Estrogen mediates many of its effects by signaling through the estrogen receptors ERα and ERβ, which exhibit overlapping expression patterns, and regulate masculinization of the brain and behavior in a complex, redundant manner (Bodo et al., 2006; Ogawa et al., 1999; Ogawa et al., 2000; Ogawa et al., 2004; Perez et al., 2003; Rissman et al., 1997). The role of a third estrogen receptor, GPR30, in male behaviors is presently unknown (Revankar et al., 2005

Another problem with the med student's theory is that puberty of adolescence is not the first time in a male child's life after his birth that he produces very high levels of testosterone that will reach and presumably impact his brain.

In the first year after birth, male humans also go through male mini puberty of infancy in which for several months their testes produce testosterone in adult amounts. So even if it were true that gender dysphoria results when a male child's brain somehow gets too much maternal estrogen during development in utero, then surely the baby's emergent "girl brain" and nascent opposite-sex gender identity would be counteracted by his brain, neurons and nervous system being flooded by the massive amount of testosterone his testes pump out for months during male mini puberty of infancy. Years before a male child would start developing secondary sex characteristics that the med student's theory says he'd sense as "errors" and would trigger gender dysphoria and a sense of being "in the wrong body," his testicles should already have generated more than enough testosterone for several months in babyhood to completely drown out and stamp out any incipient "feminized neurons" in his brain and any "girl/lady feelz" in his mind once and for all.

[–]Kai_Decadence[S] 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (1 child)

Thank you for this explanation. I will admit that there's a lot I didn't quite understand, namely the more scientific jargon but I think I'm understanding the main point which is essentially a perfectly health baby (in this case a male baby), if he does have any intervention of feminized neurons that can corrupt the brain, the testosterone will block and counter it. Is that correct?

[–]MarkTwainiac 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (0 children)

Actually, I reject the idea of "feminized" neurons - I was just using the terminology of the theory we're discussing.

The general points I was trying to make are:

1) Pregnant women's bodies don't manufacture hormones in haphazard and unpredictable ways wholly unrelated to and independent of the embryos/fetuses they are gestating at the time.

2) The hormones that pregnant women's bodies make do not get dumped in undiluted, unchanged form directly into the circulatory systems of fetuses - which is a key part of what would have to happen according to the theory that says some male and female fetuses end up developing all the anatomy and physiology customary for their sex yet somehow also develop brains/neurons/nervous systems of the opposite sex.

3) The idea that males might end up with a "feminized" brain because of exposure to too much estrogen during gestation in utero assumes that male brains are not accustomed to, and built to handle, estrogen and therefore when exposed to "excess" estrogen in utero, they end up "feminized." When in fact, male brain development and activity in utero - and throughout the rest of life - seem to be heavily dependent on and shaped by estrogen - a hormone that males naturally make in various parts of their bodies (testes, adrenals, fat and the brain). The main way that males make estrogen is by turning some of the testosterone originally produced in their testes into estrogen through aromatization (the same process that takes place in the placenta during pregnancy with a female fetus to turn the mother's elevated testosterone into estrogen).

There is a complex interplay between the blood chemistry, and the hormones, of pregnant women and fetuses; but each fetus makes its own endogenous sex hormones from its own gonads (ovaries or testes) and its own adrenal glands and those internally-made hormones (and the fetuses own genetics) are the dominant drivers of sex development. In other words, fetuses are not mere repositories that maternal hormones are poured into. In fact, fetuses are not mainly repositories for maternal hormones at all.

How a fetus develops in terms of sex appears to be primarily and most strongly affected and determined by the endogenous hormones that each fetus makes by and for itself - along with the other aspects inherent to the fetus itself, such as whether it has male or female DNA in each cell, whether it has male or female hormone receptors and physiology, and the fetus's own genetic profile/DNA, which is different to the genetic profile/DNA of the mother.

There is no evidence that if/when the ovaries, adrenals and fat of pregnant women's bodies make hormones that are atypical for pregnant women carrying a fetus of either sex that this leads to atypical physical or psychological development in the fetus.

A maternal hormone "imbalance" such as low progesterone might lead a pregnant woman to have a miscarriage. Higher than usual maternally-generated testosterone has been shown to be linked to premature birth and smaller-than-usual, low birthweight babies - this is because high testosterone (especially chronically as in PCOS) diminishes the elasticity of the uterus, reducing its ability expand to typical full-size in the latest weeks of pregnancy. But there is no evidence whatsoever that maternal hormones that are atypical, imbalanced, or go up in down in various combinations during fetal development somehow end up inside fetuses where they cause "surges," "spikes" and "washes" of opposite-sex hormones to rain down on the fetal brain cells, leading the fetus to develop a brain-body mismatch that will evince many years later.

But assuming just for the sake of argument that a male baby could be born with a "feminized" brain because his mother had hinky hormones when he was developing in utero, then yes I would think the impact of what happened to that child in utero would definitely be largely or entirely counteracted by the fact that in the first year of life all male babies go through male mini puberty of infancy, a 4-7 months-long period when their testes pump out huge amount of testosterone and their entire bodies including their brains are bathed/steeped in all that T. As anyone who has ever been around babies knows, the development that they undergo week by week after birth is really dramatic - and post-natal development in infancy and early childhood is at least as important as pre-natal development, in fact probably more so.

[–]Bright_painting 5 insightful - 2 fun5 insightful - 1 fun6 insightful - 2 fun -  (1 child)

Well, there is MINIMAL differences between a female and male brain. This have been observed mostly in the distribution of white and grey brain matter and might be the reason that women, as a group, have it easier to multitask, while men, in general, have an easier time thinking abstractly. From what I have read, there's no parts in the brain or nervous system that looks distinctively different depending on your sex, so I suspect that this med student is grasping at straws to try and give the gender ideology credibility.

[–]Kai_Decadence[S] 4 insightful - 2 fun4 insightful - 1 fun5 insightful - 2 fun -  (0 children)

Hm I see. So it's really just a non-conclusive theory at this point? And even with that, it just ties back to the "what did these brains look like" before they developed life experience type of deal.

[–]Challenge 3 insightful - 2 fun3 insightful - 1 fun4 insightful - 2 fun -  (1 child)

  1. He's basically just saying he believes in an innate gender identity, with no evidence.
  2. Even if male and female brains were significantly different, that wouldn't imply the existence of a mechanism which verifies the brain is in the correct body. There is no evidence of such, and no reason or sense that such a mechanism would evolve.
  3. Wait so he's saying the other 79 genders aren't real? The transphobic monster!

[–]Kai_Decadence[S] 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (0 children)

I see, I knew something wasn't adding up... It's once again, science fiction and for these "tests" to have validity, you'd have to run them on infants the moment they are born which is just unethical.

Wait so he's saying the other 79 genders aren't real? The transphobic monster!


[–]penelopekitty 3 insightful - 2 fun3 insightful - 1 fun4 insightful - 2 fun -  (1 child)

There is no proof of this. It's an unsubstantiated theory.

[–]Kai_Decadence[S] 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (0 children)

Yeah after hearing some other explanations, this is so true haha.