I am not sure if you are asking about the raw materials source or the supplier/manufacturer. Dr. Peat and associates would know the name of the supplier.
Just to clarify: “bio-identical” progesterone has the chemical structure as the progesterone found in mammalian placentas and blood. When the term “natural progesterone” is used, it “should” mean bio-identical progesterone. Natural here means the same chemical composition as in humans, rather than extracted from mammals. The wikipedia reference describes the two general methods for synthesizing bio-identical progesterone.
I am pretty sure that the progesterone/vitamin E oil, the compounding pharmacy progesterone creams and others all use bio-identical/natural progesterone. Plant-derived semi-synthesis into bio-identical/natural progesterone makes a beneficial substance. (Dr. Peat’s use of vitamin E as vehicle for progesterone delivery is very helpful, in my experience.) It would be very expensive to extract large amounts of progesterone from animals.
It is a good and important point that there is plenty of confusion and misleading about the relation of real progesterone to both the progestins (“synthetic progesterones”) and the Dioscorea/Mexican wild yam. Some alleged dangers attributed to natural progesterone are really due to progestins. To his credit, John Lee (who first learned about progesterone benefits from Dr. Peat) discusses this in his books. Many physicians still use “progesterone” incorrectly to mis-identify synthetic compounds that have some chemical relation, but far different effect from bio-identical progesterone.
Also, some of the advocates for herbal wild yam have used the chemical relation of the yam’s diosgenin extract to progesterone to suggest health benefits. There is some evidence to suggest the wild yam has an estrogenic (rather than progesterone) effect.
Yen ML, Su JL, Chien CL, Tseng KW, Yang CY, Chen WF, Chang CC, Kuo ML. Mol Pharmacol. 2005 Oct;68(4):1061-73. Diosgenin induces hypoxia-inducible factor-1 activation and angiogenesis through estrogen receptor-related phosphatidylinositol 3-kinase/Akt and p38 mitogen-activated protein kinase pathways in osteoblasts.
Yen ML, Su JL, Chien CL, Tseng KW, Yang CY, Chen WF, Chang CC, Kuo ML.
“an estrogen receptor binding assay revealed that diosgenin has the strong ability to replace [(3)H]estradiol bound to estrogen receptor (IC(50), 10 nM). In addition, the specific estrogen receptor antagonists ICI 182,780 (faslodex) and tamoxifen were noted to be able to strongly inhibit diosgenin-induced, src kinase-dependent Akt and p38 MAPK activation.”
Benghuzzi H, Tucci M, Eckie R, Hughes J. Biomed Sci Instrum. 2003;39:335-40.
The effects of sustained delivery of diosgenin on the adrenal gland of female rats.
“Histopathological evaluation of the adrenal gland revealed an increase in the cortical and medullary adrenal areas of the ovariectomized group and a significant decrease in these areas in the diosgenin treated animals (p < 0.001). The information is considered important because reduction in adrenal mass may poses a potential for major endocrine complications.”