Just some thinking about hormones

[Hopeful1]

Sorry if this is already posted elsewhere, I'm mostly thinking out loud here, trying to understand how this hormone thing works.

What I understand about the feedback mechanisms in the menstrual cycle:

On CD1 the levels of estrogen, progesterone and testosterone are all low. The low levels of these hormones cause the hypothalamus to produce GnRH which stimulates the pituitary to produce FSH which stimulates the growth of follicles in the ovaries.

The developing follicles produce estrogen (from testosterone produced from cholesterol), which stimulates the development of the uterine lining. Once estrogen reaches a certain level it stimulates the pituitary to produce LH which causes the follicle to mature and then ovulate. (aka-low levels of estrogen stimulate FSH production while high levels stimulate LH production).

The corpus luteum then produces progesterone (from cholesterol), which stops the pituitary from producing LH and FSH. Progesterone is produced through the luteal phase until the corpus luteum collapses, then progesterone production is stopped and it triggers the start of the next cycle.

I found a graph of the pathway to create testosterone:
One part of the pathway goes: cholesterol -> pregnenolone -> testosterone -> estradiol
The other goes: cholesterol -> pregnenolone -> progesterone

It looks like progesterone competes with testosterone for use of cholesterol. If that is true, then increasing progesterone production would decrease testosterone production and therefore estrogen production because testosterone creates estrogen. Excess estrogen would diminish progesterone because of the FSH/LH feedback mechanism. Too much estrogen would interfere with that loop (not enough FSH produced to create healthy follicles which means not enough estrogen produced to create a proper LH surge...aka the PCOS problem) and create poor corpus luteums and therefore poor progesterone production and by extension increase testosterone production.

Impacting the production of progesterone could affect testosterone levels. Increasing progesterone production could reduce the amount of testosterone produced and vice versa.

Interestingly, in the same graph it showed that cortisol is a subpathway along both the testosterone path AND the progesterone path. So if excess cortisol is produced then both testosterone AND progesterone production is diminished.

[Hopeful1]

So....if I understand the TW theory of maternal condition (big IF here) then this could be the pathway that is affected and the relative levels of these hormones are what create the environment/egg receptors/whatever that leads to preference of one gender over another. A woman who has a lot of cholesterol could produce large amounts of both testosterone/estrogen AND progesterone, leading to healthier follicles, healthier ovulations, healthier corpus luteums, healthier uterine linings. Whereas a woman who has low cholesterol and/or significant stress (cortisol) would have lower levels of both progesterone and testosterone/estrogen OR would have to choose which pathway to pursue. This would by definition lower their fertility.

So this makes sense that the level of testosterone (the middle man between progesterone and estrogen) would determine which gender would be conceived because it is the limiting factor and is present in greatest concentrations within the follicle itself.

[Hopeful1]

Also, exercise could have a secondary function besides lowering testosterone and that is lowering cholesterol. Vigorous exercise has been shown to significantly lower cholesterol as opposed to moderate exercise which does not have a significant effect on cholesterol.

[Cauliflower]

Wow, you have really done some research! Well done!
I doubt that it is that simple, many factors playing in here, one to mention sperm quality and number which sways and is not influenced by any of that.
Too low supply of cholesterol and too low hormones will make it hard to get PG and stay pregnant, so there must be a limit here. Excited to see what Atomic has to say

[Hopeful1]

Wow, you have really done some research! Well done!
I doubt that it is that simple, many factors playing in here, one to mention sperm quality and number which sways and is not influenced by any of that.
Too low supply of cholesterol and too low hormones will make it hard to get PG and stay pregnant, so there must be a limit here. Excited to see what Atomic has to say

Thank you! I think better when I can talk or write things out. But you are absolutely right-it is probably not this simple, it does not address daddy's part in the equation at all and it doesn't take into account that all these hormones are made in different parts of the body, not just the ovaries. Plus, each stop on this pathway relies on enzymes and cofactors that may affect the system in various ways. For example, the production of estrogen from testosterone requires aromatase and a methyl group holder (most likely a B vitamin such as folic acid or B12). The level of aromatase in your system is determined by genetics and the levels of the cofactors are effected by your diet and the needs of other enzymes in your system.

I think, though, that if the pathway can be determined then things do become significantly more simple in that each individual can figure out where along the pathway they need to make changes.

And you are also right that you need a certain level of cholesterol and hormones in order to get pregnant at all. I am infertile, so this is actually really interesting to me. I ovulate late and have borderline low progesterone (no PCOS or high T). I am thinking that cortisol (I am highly anxious and extremely easily stressed) is high-jacking my progesterone and leading to a poor FSH/LH response-I'm just not making enough hormones to have a good ovulation. I had a year of fertility treatments back in 06 and I responded really well to the FSH, but after around CD 12 my follicles would slowly stop developing. I think I have a good response to FSH because my estrogen is low but I don't produce ENOUGH estrogen to make the LH surge and then the follicles wither and aren't able to produce good quality progesterone.

I DID get pregnant in 08, after spending almost a year out of work, meditating daily, exercising, writing, living rent-free in a relatives vacation home by a beautiful lake. My cortisol levels were probably really low at that point, giving my body the ability to make appropriate levels of hormones.

I don't know whether this changes anything or is even new information to anyone else, I just find it helpful to figure out what is going on in my own wacky body. :P

[atomic sagebrush]

Yes that's exactly right. That is what my "fertility theory of swaying" rests on.

Therein lies the problem with the traditional theories of swaying - they are not supported by biology. Telling someone "eat eggs to raise your progesterone" because progesterone supposedly sways pink is impossible and a terrible idea because if your body "thinks" it needs testosterone in order to survive, it will make testosterone out of the last scrap of cholesterol it can get its hands on at the expense of progesterone.

Here is an essay you might be interested in. http://genderdreaming.com/forum/gend...ly-demand.html