Estrogen dehydroepiandrosterone conversion

In most mammals, estrogens (female sex steroid hormones) are synthesized from cholesterol using the parent ring structure, cyclopentanoperhydrophenan-threne of the estrane series. The steroidogenic pathway includes the production of the androgenic precursors dehydroepiandrosterone and androstenedione, the latter of which is converted to testosterone, then to estradiol-17/i. This requires aromatization of these andogenic precursors by an aromatase enzyme complex. The major source of estrogen in postmenopausal women is the conversion of androstenedione to estrone by aromatase activity... 

One of the more readily available plant steroids, dehydroepiandrosterone (DHEA), provides the raw material for conversion to estrone. An early step in converting steroids from plant sources to starting material for modified estrogens comprises obligate expulsion of the methyl group at position 10 that blocks aromatization of the A-ring. 

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