Estriol,urinary

Reifenstein and Dempseyl9 using Talbot s colorimetric method found the urinary "estrone" to vary from 10 to 39 ig. per day in 5 normal women and from 27 to 40 ig. per day for 5 normal men. Attention was not paid to the question of whether the observed differences were primarily inter-individual. In another study20 involving 3 men and 2 women, Pincus found about a 12-fold variation between the two women. One woman excreted over a period of several days estradiol + estrone + estriol to the extent of 155.2 ig. per day for the other woman and the 3 men, the corresponding values were respectively 13.4 ig., 12.4 ig., 7.6 ig. and 16.8 ig. 

The use of GC for the determination of estriol was suggested in the early years of GC. But it was not until later that gas chromatographic methods of urinary extriol were established. 

Estriol (estra-1,3,5(10)-trien-3,16-a,17-8 -triol) is the major estrogen metabolite found in the urine. It is excreted in the form of its conjugate with glucuronic acid. The determination of this steroid as an index of placental function has become one of the most widely used endocrine determinations. As pregnancy progresses, the excretion increases and reaches very high levels near term. In abnormal fetoplacental function, the levels of estriol will fall in some cases. The fall is usually progressive, and, because of this, serial determinations of urinary estriol must be carried out. The drop in estriol can be taken as evidence of placental insufficiency, and close watch by the physician is indicated, as a continued drop may necessitate Cesarean section to save the life of the infant. 

The same assay procedure should be used for specimens from an individual. Some background in the use of urinary estriol as an index of placental function may be found in a number of reports on the use of this valuable clinical chemistry tool in obstetrics. More recently, Wolff et al. (5) reviewed the various pathologies and abnormalities of pregnancy versus values of estriol levels in urine. 

Recently values and procedures for the determination of estriol in amniotic fluid were described (7, 8). In some instances, it may be easier to obtain a sample of amniotic fluid than a 24-hr urine, depending on experience. There is a correlation between urinary and amniotic fluid estriol levels. After 20 weeks gestation, amniotic levels show a progressive increase with slopes similar to the urinary estriol which increases throughout gestation, and for this reason, the methodology is included here. 

Amniotic fluid contains estriol in a variety of forms notably free, sulfate, and glucuronide. Therefore the determination is for total estriol content. After extraction, the procedure is the same as just described for the urinary estriol. 

Measurement of urinary and serum estriol (E3), once used to assess fetal well-being, is no longer recommended for that... 

The estriol route is the most significant, judging from the fact that estriol is the major urinary estrogen in humans. As its name suggests, estriol contains three hydroxyl groups, two of which are identical to those of estradiol (3, 11 ), but the third is unique to estriol, a 16a-hydroxyl group that is attached to either estrone or estradiol. Estriol formation is increased in obesity and hypothyroidism, and is decreased in hyperthyroidism. Catecholestrogen formation is catalyzed by a 2-hydroxylase that is present in the liver, nerve cells, and other tissues, and both estrone and estradiol... 

Ahlstrom K, Sandahl B, Sjoberg B, et al. Effect of combined treatment with phenylpropanolamine and estriol, compared with estriol treatment alone, in postmenopausal women with stress urinary incontinence. Gynecol Obstet Invest 1990 30 37-43. 

Raz R, Stamm WE. A controlled trial of intravaginal estriol in postmenopausal women with recurrent urinary tract infections. N Engl J Med 1993 329 753-756. 

The best method for urinary estrogens of clinical importance is that devised by Brown (B20, B21). This depends on the modification of the Kober-Ittrich color reaction to provide an extremely sensitive fluorescence reaction (see also S2). Acid hydrolysis (15 minutes) is followed by either extraction (2X1 volume) evaporation to dryness a partition between petroleum ether-benzene and water (estriol) and 1.6% NaOH (estradiol, estrone). The two solutions are methylated (10 minutes) and extracted with ether the ether is evaporated, and the residues are run on alumina columns. In the original procedure the less specific and sensitive form of the Kober reaction required more extensive purification one technician could complete four estimations in 1.5-2 days. The new procedure enables four determinations to be made every 5-6 hours. An ultrarapid version of this method for specialized obstetric use has been devised by Gemzell and his group and will be published shortly. By this method, twelve samples can be measured in 3 hours by one technician. 

The first indication of possible adrenal hypoplasia in an infant studied by the authors was the finding of an abnormally low level of estriol in plasma obtained from the mother prior to delivery. The urinary excretion of 16a-OH-DHA, 16-oxo-androstenediol, and 16a-OH-pregnenolone was only about one-tenth that expected for normal newborn infants. This infant died of respiratory failure 30 hours after birth postmortem examination showed very small adrenal glands. 

Schwers, J., Gurpide, E., Vande Wiele, R. L., and Lieberman, S., Urinary metabolites of estradiol and estriol administered intra-amniotioally. J. Clin. Endocrinol. Metah. 27, 1403-1408 (1967). 

In summary, the use of DPP and an electroactive label resulted in a competitive homogeneous immunoassay with a detection limit in the 100 ng/ml range. Although application to estriol is not feasible, the direct analysis of urinary samples for other analytes in this concentration range would be possible. The analysis of plasma analytes may or may not require a cleanup step, depending on the analyte involved. 

Wniman K, Pulkkinen MO. Reduced maternal plaana and urinary estriol durii ampicillin treatment Am J Obstet Gynecol ( 97 ) 109, 893-6. 

When estratetraenol is administered to human subjects, a considerable increase in the urinary estriol fraction is observed (Stimmel, 1957a). Further investigation revealed that the estriol fraction contained 16,17-epiestriol (Stimmel and Notchev, 1961 Knuppen and Breuer, 1962b). 

High excretion of 3j5-hydroxy-5-ene steroids in pregnancy urine. Low urinary estriol excretion... 

Fig. 2. Estrogens. Steroid metabolism in the fetoplacental unit. Plasma estriol levels are determined by fetal metabolism, so that maternal urinary or plasma estriol levels provide an index of fetal health.

Gas Chromatographic Technique for Rapid Determination of Urinary Estriol During Pregnancy... 

II. Rapid Estimation of Urinary Estriol by Gas Chromatography During the Last Two Trimesters of Pregnancy... 

Validation of Methods for Determination of Urinary Estriol During Pregnancy Using Mass Fragmentography Clin. Chim. Acta 62(3) 385-392 (1975) CA 83 143947p... 

Rapid Method for Gas Chromatographic Determination of Urinary Estriol Horumon To Rinsho 17(9) 750-756... 

Rapid Gas-Liquid Chromatographic Method for the Quantitation of Urinary Estrone, 17B-Estradiol, Estriol, and Pregnanediol Throughout Pregnancy... 

The Quantification of Free Urinary Estriol in the Human Female by Gas-Liquid Ghromatography 5th Midwest Regional Mtg., AGS,... 

Scommegna, A., and Chattoraj, S. C. Clinical Application of a Gas Chromatographic Technique for Pregnancy Urinary Estriol Estimations... 

Determination of Urinary Estriol in Late Pregnancy by Gas-Liquid Chromatography... 

Tanaka, S., Satake, M., and Sakai, K. Rapid Gas Chromatographic Determination of Urinary Estriol in the End Stage of Pregnancy... 

Tikkanen, M. J., and Adlercreutz, H. Method for the Quantitative Determination of Urinary Estriol Conjugates in Human Pregnancy... 

---