AN ALGORITHM FOR DETERMINING GESTATIONAL-AGE FROM UNCONJUGATED ESTRIOL LEVELS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 56  (5) , 649-655
Abstract
Between the 30th-40th wk of gestational age (GA), plasma unconjugated estriol concentrations plotted as logarithmic function of GA describe a complex bimodal curve. The maximum concentrations for the 1st peak occur at .apprx. 34 wk GA, those for the 2nd peak occur at .apprx. 38 wk GA and a between-mode nadir occurs at 35 wk GA. Using the close relationship between the features of this curve and GA, a computerized algorithmic curve analysis is devised for the estimation of GA during the 3rd trimester of pregnancy. This report describes the algorithm, its clinical application and its preliminary performance.