The combined tests of overnight 12-hour urine E3/C ratio and fetal heart rate in perinatal monitoring.

Using perinatal monitoring, we evaluated retrospectively 793 late pregnancies with regard to the overnight 12-hour urine estriol/creatinine ratio (E3/C) and fetal heart rate (FHR). The results revealed that 1) FHR corrected the false positive rate of E3/C by 13.7% (93/677); 2) E3/C gave reliable results in perinatal prediction in 81 of the 116 suspicious FHR cases (70%, 81/116); 3) When both tests were abnormal the incidence of poor perinatal results increased by 83.7% (36/43), and the perinatal mortality (7%, 3/43) in patients with abnormal values in both methods was 35 times higher than that in patients with normal results in both tests (0.2%, 1/462); 4) Both negative FHR test and normal E3/C could be reassured, as the risk of death in uterus within a week of both normal tests was only 0.13% (1/793). It is suggested that the E3/C may be used as a first line test for perinatal monitoring, where E3/C value is lower than normal, FHR test is added to increase the reliability of perinatal diagnosis, especially in the moderate and severe hypertensive disorders of pregnancy.