Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to Estriol: estradiol, estrone


C18H24O3 A crystalline estrogenic hormone obtained from human pregnancy urine.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



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).

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Gaspar and colleagues recruited 50 postmenopausal women with GSM and assigned 25 participants to 2 weeks of pretreatment with estriol ovules 3 times per week (for epithelial hydration) followed by 3 sessions of Er:YAG nonablative laser treatments; 25 women in the active control group received treatment with estriol ovules over 8 weeks.
Maternal serum median levels of alpha-foetoprotein, human chorionic gonadotropin and unconjugated estriol in second trimester in pregnant women from north-west India.
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.1 We aimed to define if there is any relationship between second trimester serum markers and neonatal severe hyperbilirubinemia to protect the neonates from its neurological damage.
[E.sub.1]: estrone; [E.sub.2]: estradiol; [E.sub.3]: estriol; 2-[OHE.sub.1]: 2-hydroxyestrone; 2-[OHE.sub.2]: 2-hydroxyestradiol; 16a-[OHE.sub.1]: 16a-hydroxyestrone.
The research also showed that taking estriol plus Copaxone conveyed significant positive benefits in the women's scores on cognition tests.
After one year of treating 158 women in 16 sites across the U.S., researchers found that those who were given estriol showed a relapse rate 47% lower than the those who were given a placebo.
On the basis of the manufacturers' literature (IMMULITE 2000 Unconjugated Estriol, PIL2KU[E.sub.3]-4,2010), both the Access and IMMULITE immunoassays use calibrators that are traceable to values assigned by the GC-MS reference method, and there are good correlations among the methods, e.g., IMMULITE 2000 = 1.01 (Beckman) -0.01 ng/mL (r = 0.980); IMMULITE 2000 = 0.98 (GCMS) + 0.02 ng/mL (r = 0.954).
(8,9) Currently, the best second-trimester test is the quadruple test (AFP, unconjugated estriol, hCG [total or free [beta]-hCG], and inhibin-A) with an 80% detection rate at a 5% false-positive rate.
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).
The association between DS and low maternal serum alpha-fetoprotein (MSAFP) levels in the second trimester was recognized in 1984.5 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.