Comparison of an all-aqueous automated urine pregnancy oestrogen method with one using organic solvent extraction

Maternal Plasma Free Oestriol and 24 Hour Urinary Oestriol Excretion in the Assessment of Foetal Outcome

“…Some authors (Shelley et al 1970;Powers and Roach 1974) have suggested that oestrogen/creatinine ratios could be used to overcome the diurnal vari¬ ations, but the results have not been convincing. Recently, auto¬ matic procedures with a high precision and clinical reliability have been reported (Moscrop et al 1974;Little et al 1975). Up to now the majority of results reported in the literature have been obtained by methods involving hydrolysis of urine, extraction and separation of the phenolic fraction, and colorimetry, photometry, fluorometry or gas-liquid chromatography.…”

Review article

“…The most recent developments are based on the performance of KOBER color reaction directly on urine followed by ITTRICH extraction and fluorimetry [15]. This permits the use of automated, continuous-flow Systems which allow up to 70 or more samples to be assayed each day with a high degree of precision [71,88] and clinicäl reliability [51 ]. It also seems to be the most accurate method, in terms of precision between different laboratories [91].…”

Screening for Fetal Risk With Urinary Oestrogen: Creatinine Ratio at 34 Weeks

“…Urinary total oestrogens (pmol/l) and creatinine (mmol/l) were measured by combining an all-aqueous automated continuous flow method for oestrogens (Little et al, 1975) with simultaneous measurement of creatinine. Data were transformed to log,, for calculation of the OjC ratio to facilitate comparison of values throughout the reference range (Phillips et al, 1978).…”