[Fetal well-being monitoring: comparison between a new method of serum estriol assaying and determination of urinary estriol/creatinine].

Normal pregnant serum E3 values were measured in 2,611 women non less than or equal to 13 to 41 gestational weeks, by a new method of serum free E 3 (SFE 3) determination on radioimmunoassay kit. Normal values of SFE3 from the less than or equal to 13 to the 41 gestational week and the normal low-limit of each week were established; Blood and randomized urinary (RU) samples were obtained simultaneously from 392 women in late pregnancies for comparison of fetal monitoring validity. The results of the determinations of SFE3 and RUE3/C revealed: (1) The coefficient of correlation in RUE3/C with SFE3 was close in either normal or high-risk pregnancies (P less than 0.001); (2) SFE3 straightened out false positive rate of RUE3/C by 92%. Among the false positive rates of RUE3/C pregnancy-induced hypertension (PIH) has the highest 53.6% as compared with other high-risk pregnancies; (3) The correct rate of SFE3 in predicting fetal well-being 95.6% was significantly higher than that of RUE3/C (87.3%) (P less than 0.001). Our observations suggest that RUE3/C may be used as preliminary perinatal monitoring. When RUE3/C value is below the normal, SFE3 test is employed to ensure the reliability of perinatal diagnosis, especially in PIH. Clearly, the combination of these two tests would be better than the use of any of them.