Urinary Estriol Determinations Research Articles

Oxytocin challenge tests and urinary estriols in the management of high-risk pregnancies.

Three hundred sixty-two pregnant patients at risk for placental insufficiency were evaluated with the oxytocin challenge test (OCT) and urinary estriol determinations. The perinatal mortality in patients with positive tests was 6 times higher than the perinatal mortality in patients with negative tests. Expectant treatment of patients with a positive OCT was associated with a perinatal mortality 6 times higher than if immediate delivery was accomplished. A negative stress test was reassuring, as the risk of death in utero within a week of a negative test was only 0.3%. The combination of low estriol levels and positive OCT was quite ominous, while the presence of normal estriol levels provided reassurance of good perinatal outcome when expectant treatment of a patient with a positive OCT was undertaken. The overall perinatal mortality of the patients in this study was not different from that in the general obstetric population.

Determination of urinary placental estriol by reversed-phase liquid chromatography with fluorescence detection.

Abstract We describe a liquid-chromatographic procedure for determining urinary estriol concentrations. The urine sample, after enzymatic hydrolysis to free the conjugated estrogen, is extracted with ether, and an aliquot of the resulting extraction residue is injected into the liquid chromatograph. Sample components are separated with a reversed-phase C18 column and isocratic elution with an acetonitrile/water mobile phase. Using a far-ultraviolet excitation wavelength, we measure the natural fluorescence of the eluted estrogen with a fluorescence detector. The procedure provides excellent sensitivity for determing near-term pregnancy concentrations of urinary estriol. The selectivity of the method limits the effect of potentially interfering compounds.

Determination of urinary placental estriol by reversed-phase liquid chromatography with fluorescence detection.

Ww describe a liquid-chromatographic procedure for determining urinary estriol concentrations. The urine sample, after enzymatic hydrolysis to free the conjugated estrogen, is extracted with ether, and an aliquot of the resulting extraction residue is injected into the liquid chromatograph. Sample components are separated with a reversed-phase C18 column and isocratic elution with an acetonitrile/water mobile phase. Using a far-ultraviolet excitation wavelength, we measure the natural fluorescence of the eluted estrogen with a fluorescence detector. The procedure provides excellent sensitivity for determing near-term pregnancy concentrations of urinary estriol. The selectivity of the method limits the effect of potentially interfering compounds.

A fast, simple colorimetric determination of total urinary estrogen

A relatively rapid simplified colorimetric method which uses an enzymatic hydrolysis for the determination of total urinary estriol is described. All reagents and the enzyme preparation are prepared within the laboratory. Thus not only is reagent quality readily controlled but a marked cost saving is obtained with respect to the method's commercial counterparts. A comparative study of the hydrolytic ability of β-glucuronidase from E. coli and Helix pomatia indicated the latter to be the enzyme of choice for the proposed methodology. The proposed method was found to be linear to greater than 20 μg estriol/ml with coefficients of variation of 1.6 and 2.4% for 24-hr urinary estriol concentrations of 18.7 and 29.6 mg, respectively. A comparative study between the described method and a colorimetric method using an acid hydrolysis indicated the latter to yield only 80% of the total urinary estriol obtained with the former.

Mechanism for interference of hydrochlorothiazide with the Kober reaction for determination of urinary estriol in pregnancy

Investigation of the mechanism of the lowering effect of hydrochlorothiazide, which was administered orally, in the determination of estriol from the pregnancy urine has been carried out. The isolation and determination of the structure of a copolymer formed from estriol and formaldehyde have suggested the mechanism by which, during the acid hydrolysis process of the glucuronide conjugate of estriol, some copolymers of estriol and formaldehyde generated from hydrochlorothiazide, were formed, thus lowering the observed values of the estriol contents in the urine.

Management and outcome of pregnancy in diabetes mellitus, Classes B to R

During the period 1971 to 1975, 260 women with diabetes mellitus, Classes B through R, were delivered of their infants at Los Angeles County Women's Hospital. The plan of patient management included frequent clinic visits and hospitilization to assure good control. A program of intensive antepartum fetal surveillance was begun at 34 weeks' gestation, with the use of daily 24 hour urinary estriol determinations and a weekly contraction stress test (CST). A lecithin/sphingomyelin ratio was evaluated for all patients before elective delivery. The perinatal mortality rate in these diabetic pregnant women was 46 per 1,000 as compared to 24 per 1,000 in the general population. Only three stillbirths occurred in the diabetic group, none within one week of a negative CST. Congenital malformations were responsible for almost half of the neonatal deaths. There were no deaths due to iatrogenic prematurity or trauma. Mean gestational age at delivery was 37.9 weeks and vaginal delivery was the mode for approximately half of the women. Two thirds of the infants did experience some morbidity.

Determination of urinary estriol by radioimmunoassay. Modification of a commercial kit for serum analyses

A simple and rapid method for urinary estriol determination is described. Modification of a commercially available kit for serum estriol gives a method for urinary estriol determination with a capacity of approximately 75 determinations a day. A high degree of accurary was revealed by indirect comparison with a mass fragmentographic method.

Urinary Estriol for Assessment of Fetoplacental Function

A total of 1,607 urinary estriol determinations were performed in 447 patients with normal and complicated pregnancies. In general, the test provided reliable information concerning fetal status, particularly in pregnancies complicated by toxemia, diabetes, and postmaturity. When measured consecutively, a drop of 50% or more in estriol level usually should be considered a significant index of fetal distress. Limitations of the test and several compensatory measures aimed at minimizing inaccuracy are discussed.

Urinary estriol determinations in normal and pathological pregnancies.

Urinary estriol determinations in normal and pathological pregnancies.

Serial Estriol Determinations in High-Risk Pregnancies:

Urinary estriol determinations have gained popularity as an indicator of the status of the fetoplacental unit. The author describes their use in high-risk pregnancies as a tool with two primary functions: 1) to confirm fetal well-being, or 2) to supply guidelines for intervention when fetal well-being is in doubt. Research in the area is also reviewed. Simple steps for patient counseling are given on an “Instruction Sheet,” and other implications for primary care nursing me discussed.

Validation of methods for determination of urinary estriol during pregnancy using mass fragmentography

A specific and accurate method for determination of urinary estriol during pregnancy is described. After acid hydrolysis of 1 ml urine, a fixed amount of [2,4- 2H 2] estriol (usually 15 μg) is added and the mixture is extracted with diethyl ether. The extracted estriol is converted into the tri-trimethylsilyl derivative and the amount of unlabeled estriol is determined from the ratio between the recordings at m/ e 504 and m/ e 506 obtained after analysis with a gas chromatograph-mass spectrometer equipped with an MID (multiple ion detector). The two ions used correspond to the molecular peak in the mass spectrum of unlabeled and (2,4- 2H 2)-labeled tri-trimethylsilyl derivative, respectively. The relative standard deviation of the method was about 6%. The method was compared with a photometric method using the Kober reaction and the gas liquid Chromatographic method used in routine analysis. There was a good correlation in both cases and the regression coefficient was 1.5 and 1.3, respectively.

Standardisation of urinary estriol determinations during pregnancy

Estriol occurs in urine as water-soluble conjugates, but water-insoluble estriol is usually used as a primary standard to calibrate analytical methods. Estriol solutions in ethanol cannot be carried through commonly used methods and are therefore unsatisfactory. With caution, estriol in aqueous NaOH can be used in most methods except those involving separation of conjugates on columns. Estriol sulfonates are only satisfactory in direct methods which do not involve preliminary purification steps. Concentrates of partially purified conjugates are easily prepared, and these could be used as reliable secondary standards in all methods provided that they are accurately calibrated.

The oxytocin challenge test

It has been suggested that applying standard stress with oxytocin during the antenatal period may be of use in assessing fetal well-being or its ability to withstand labor. The oxytocin challenge test was applied to a group of 50 high-risk Obstetric patients, and the results were correlated with urinary estriol determinations, the occurrence of fetal distress in labor, Apgar scores, and their high-risk index. Thirty-five patients had negative tests, 9 had positive tests, and 6 had only unsatisfactory tests. There was no correlation between a positive test and low estriol levels, the occurrence of fetal distress in labor, or Apgar scores. However, the results suggest a negative test in a high-risk pregnancy may be a guide to allow the pregnancy to continue.

A gas chromatographic technique for rapid determination of urinary estriol during pregnancy

A very rapid and specific assay is described for the determination of the urinary estriol during pregnancy. It involves rapid enzymatic hydrolysis, ether extraction, solvent partition and final estimation of estriol as trimethylsilyl ether in a gas Chromatograph. Up to 25 samples can be processed in duplicate per day. For one sample, the result can be obtained within 2.5 h after receiving the urine specimen. The method is sensitive enough to determine estriol level less than 1mg/l. Specificity has been tested using a mass spectrometer.

Hydrochlorothiazide Interference with Urinary Estriol Determination

Abstract The commonly used diuretic, hydrochlorothiazide, interferes with the determination of urinary estriol, by destroying the latter during acid hydrolysis. Urine specimens from pregnant patients taking this diuretic may therefore show falsely low estriol values.

Use of urinary estriol determinations in high-risk pregnancy in the community hospital

Use of urinary estriol determinations in high-risk pregnancy in the community hospital

Use of urinary estriol determinations in high-risk pregnancy in the community hospital

Twenty-four-hour urinary estriol assays were done in 199 “high-risk” pregnancies. Records were reviewed to evaluate the validity and usefulness of the test in a community hospital. The correlation between estriol level obtained within 7 days of delivery and fetal survival was similar to that reported by others. Past 33 weeks of gestation, no fetal loss occurred if estriol was above 16 mg. per 24 hours, and no infants survived when estriol levels were less than 4.9 mg. per 24 hours. In 143 cases, estriol assays were helpful in clinical management. The most frequent use of the test was in allowing a pregnancy to progress to term. In 17 cases the decision to intervene was based on test results. Estriol determinations can be useful in the management of high-risk patients in a community hospital; however, it is susceptible to faulty use or misinterpretation.

Relationship between elevated blood pressure and urinary estriols during pregnancy

Serial 24 hour urinary estriol determinations have been utilized to follow over 2,000 high-risk pregnancies in this Center. Over 400 patients presenting with hypertension and/or pre-eclampsia have been studied. It is apparent that serial estriol determinations have a definite place in the management of these complications of pregnancy; they are especially useful in determining which patients may be allowed to proceed further in gestation without jeopardizing the infant or causing unnecessary prematurity by early induction of labor.

Estriol excretion in normal and complicated pregnancies

Estriol excretion patterns were studied in normal pregnancies and pregnancies complicated by hypertension and diabetes mellitus. The data reveal a significant correlation between estriol levels and fetal weight. Three distinct excretion patterns of significant prognostic value were found in the diabetic pregnancies. In this laboratory, urinary estriol determinations have been found to be a useful adjunct in the management of complicated gestations.

A new method for evaluation of urinary estriol determinations

The concept of zoning urinary estriol determinations is presented. The main advantage is that one knows immediately how values from a particular patient compare with those of other patients who are delivered of surviving infants. Pregnancies with poor fetal outcome are associated with a high percentage of cases with values falling in Zone I. The synthesis of estriol within the fetoplacental unit is reviewed and various factors which can cause decreased maternal urinary estriol excretion are discussed.