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Related to Estring: Vagifem, Femring


C18H24O2 An estrogenic hormone produced by follicle cells of the vertebrate ovary; provokes estrus and proliferation of the human endometrium, and stimulates ICSH (interstitial-cell-stimulating hormone) secretion.



C18H24O2, a female sex hormone of the estrogen group with the structural formula

Estradiol occurs as colorless crystals with a melting point of 176°–178°C. Poorly soluble in water, it dissolves better in organic solvents. It is optically active, with a specific rotation of [α]D= +81°.

Estradiol was first isolated in 1935 from the follicular fluid of the ovaries of swine by the American biochemist E. Doisy. Of all the estrogens, it has the highest physiological activity, but it is rapidly inactivated in the body. Longer-acting preparations of estradiol (estradiol dipropionate and estradiol benzoate) are obtained by the esterization of estradiol with various organic acids. Estradiol has important physiological functions (seeESTROGEN).

References in periodicals archive ?
Estring provides an alternative that contains a very low dose of estrogen applied directly to the tissues of the vagina and urinary tract.
notes that the Estring estrogen ring can be difficult and painful to remove from a patient with urogenital atrophy and a stenotic introitus.
In addition, the Canadian Competition Bureau's decision includes Pfizer's commitment to amend an existing distribution agreement in Canada related to Estring.
A similar device, Estring, is approved for treating urogenital symptoms associated with postmenopausal atrophy of the vagina or lower urinary tract.