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Related to Estriol: estradiol, estrone


C18H24O3 A crystalline estrogenic hormone obtained from human pregnancy urine.



C18H24O3, a female sex hormone of the estrogen group with the chemical formula

Estriol occurs as colorless crystals with a melting point of 280°C. It is readily soluble in organic solvents. Optically active, it has a specific rotation of [α]D = +61°. Estriol was first isolated in 1934 from the urine of pregnant women. The hormone is ten to 15 times weaker in its physiological activity than estrone, from which it may be easily obtained semisynthetically.

In humans, dogs, and rats, estriol is one of the end products of the metabolism of estrogen. Estriol has also been discovered in the fruits and flowers of certain plants, including the willow, milkweed, and wheat. Seasonal changes or unusual local conditions sometimes cause an increase in the amount of the hormone contained in forage grasses. As a result, cattle may suffer from certain diseases or may produce less milk, since estriol inhibits lactation. Estriol has important physiological functions (see).

References in periodicals archive ?
The benefits of estriol may, in part, be explained by its mixed pro-estrogenic and anti-estrogenic effects.
Because estriol constitutes 60-70% of the total estrogens during pregnancy if the fetal adrenal and liver are functional and AFP is secreted during pregnancy from the fetal liver in a very high amount.
The research also showed that taking estriol plus Copaxone conveyed significant positive benefits in the women's scores on cognition tests.
researchers found that those who were given estriol showed a relapse rate 47% lower than the those who were given a placebo.
1990), suggesting they can provide the uniquely fetal precursors for the human pregnancy estrogen, estriol.
Among those laboratories, 56% (n = 169) offered AFP alone; 30% (n = 90) offered AFP, unconjugated estriol, and hCG (the triple test); and 14% (n = 42) offered AFP and hCG (the double test).
M2 PHARMA-April 5, 2013-Synthetic Biologics Inc wins US patent covering the Estriol and Copaxone combination for MS(C)2013 M2 COMMUNICATIONS
There are three major forms of estrogen that occur naturally in the human body: 1) estrone (E1); 2) estradiol (E2); and 3) estriol (E3).
5 This association was expanded in the late 1980s, when elevated levels of human chorionic gonadotropin (hCG) and decreased levels of unconjugated estriol were also reported in DS fetuses.