Estriol is a steroid hormone that is the main estrogen in pregnant women, and is only present at very low levels in non-pregnant women. It has historically been considered a much weaker estrogen than estradiol (R).
Formulations containing 2% estriol in addition to 1% estradiol, 1% estrone, 20% progesterone and 5% testosterone have been demonstrated to remain stable when incorporated in 3 different cream bases and refrigerated or stored at room temperature for 6 months (R).
Estriol penetrates the skin more slowly and to a smaller extent than estradiol, estrone and progesterone (R, R, R). In an experiment on mouse skin, less than 3% of the applied estriol had penetrated the skin after 16 hours, compmared to 18% for estradiol and 11% for estrone (R). Moreover, only low concentrations of estriol reaches the dermis of human skin (R).
Unlike estrone and estradiol, only a small amount of the absorbed estriol is metabolised in mouse skin (R).
Outcome | Grade | Effect | Studies | |||||||
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Skin Elasticity |
C
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Skin Firmness |
C
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Facial Pores |
C
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Wrinkles |
C
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Skin Hydration |
C
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Outcome | Grade | Effect | Studies | |||||||
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Blood Vessels |
C
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Collagen |
C
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