According to http://www.ncbi.nlm.nih.gov/pmc/articles.../table/T1/
Red clover has kaempferol.
shows it has similar chemicals than soy, with higher levels of formononetin and biochanin A.
From what I'm thinking, ovaries should have receptors on them. Whatever downregulates/desensitizes them is a high risk. Antagonists too; agonists should also be examined. What ever the chemical is, it increases oviduct size, but it decreases ovary size.
The article "Dietary red clover (Trifolium pratense) induces oviduct growth and decreases ovary and testes growth in Japanese quail chicks" ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2858001/
reposted link) says irrigation to clover increased its phytoestrogen content that does this. It says "large amounts of the phytoestrogen biochanin A decreased fertility in scaled quail, suggesting that animals would not consume enough in the field to cause reproductive disruption " [same result for mammal grazers]. Some synthetic estrogens do this too "the potent synthetic estrogen, diethylstilbestrol (DES), decreased ovarian weight in adult scaled quail." It showed evidence that estrogenic chemicals can cause problems for rats and kangaroos too.
My worry is, what if other herbs could cause a similar problem by being the wrong kind of estrogenic or progestogenic. It is known that clover, which is a ground cover, does this to protect it from overgrazing, that may not be a problem with other plants.
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