Been thinking about pregnenolone as well; but started out with progesterone. I have probably been low for many years; according to symptoms I had before iodine. There is a relation here, as progesterone is used for PCOS, fibrocystic breast, Breast Cancer etc. I believe it can complement the iodine; both sexes, please search, men!:)
Bio-identical progesterone is not "natural" as we humans lack the enzyme needed to convert diosgenin from plants into progesterone, similar to the lack of enzyme to make ascorbic acid from glucose. So it is done in a lab where they add the enzyme. The process is not patentable. Thats why most scientific results come from the synthetic version of it; progestin etc.
What I did was similar to when I started iodine; read, read, and read more. Went to the forum where people shared their experience with it. What I saw t was that folks had to find their fit dosage before it worked properly. Also that when the progesterone hit the receptors of estrogen, the estrogen has to go somewhere. The blood tests aren't much good.
The newer saliva tests may be more accurate, but the older (good)doctors used 24 hours urine test. As with iodine.
The doctors are Wright, Lee, Ray Peat and others. Here`s a snippet from Lee;
"Rule 3. Use only in dosages that provide normal physiologic tissue levels.
The third rule is a bit more complicated. Everyone would agree, I think, that dosages of hormone supplements should restore normal physiologic levels. The question is—how do you define normal physiologic levels? Hormones do not work by just floating around in circulating blood; they work by slipping out of blood capillaries to enter cells that have the proper receptors in them. As explained above, protein-bound hormones are unable to leave blood vessels and bond with intracellular receptors. They are non-bioavailable. But they are water-soluble, and thus found in serum, whereas the “free” bioavailable hormone is lipophilic and not water soluble, thus not likely to be found in serum. Serum tests do not help you measure the “free,” bioavailable form of the hormone. The answer is saliva testing.
It is quite simple to measure the change in saliva hormone levels when hormone supplementation is given. If more physicians did that, they would find that their usual estrogen dosages create estrogen levels 8 to 10 times greater than found in normal healthy people, and that progesterone levels are not raised by giving supplements of synthetic progestin such as medroxyprogesterone acetate (MPA).
Further, saliva levels (and not serum levels) of progesterone will clearly demonstrate excellent absorption of progesterone from transdermal creams. Transdermal progesterone enters the bloodstream fully bioavailable (i.e., without being protein-bound). The progesterone increase is readily apparent in saliva testing, whereas serum will show little or no change. In fact, any rise of serum progesterone after transdermal progesterone dosing is most often a sign of excessive progesterone dosage. Saliva testing helps determine optimal dosages of supplemented steroid hormones, something that serum testing cannot do.