Paired measurements of total and unconjugated estriol in maternal plasma during the 2nd and 3rd trimester of pregnancy - their relationship to intrauterine growth retardation.

Growth retarded fetuses and neonates have higher morbidity and mortality rates than normally developed infants of comparable age [4, 5, 16, 19, 20, 24]. During the immediate neonatal period, smallfor-date infants run an increased risk of infection, are particularly prone to hypoglycemia and have difficulties in maintaining normal body temperature. Subsequently some of these infants will not attain normal body size, and a considerable number will suffer from neurologic impairment [8,10, 23]. Early detection of intrauterine growth retardation (IUGR) and careful monitoring of the affected fetuses, both by biophysical and biochemical means, are of substantial interest to the obstetrician. Once fetal growth retardation is recognized, the obstetrician will attempt to normalize fetal growth during the further course of the pregnancy by elimination of maternal causes contributing to the gestational disorder (nicotine, drug abuse, maternal malnutrition, etc.) or by intensive therapy of accompanying maternal complications (toxemia, gestational diabetes, etc?) In some cases, early delivery of a viable fetus will be accomplished before irreversible damage or death has occurred. During the 2nd and 3rd trimester of pregnancy, the major proportion of estriol circulating in maternal blood and being excreted through maternal urine and feces is synthesized in the fetoplacental unit [6, 7]. Normal maternal plasma estriol levels indicate fetal well-being, whereas abnormal estriol profiles are mostly associated with abnormal fetal development or fetal distress [14]. The study was designed to examine the possibilities of predicting fetal growth retardation äs early äs during the 2nd trimester of pregnancy by means of total and unconjugated estriol assay in maternal plasma and to compare the usefulness of these two feto-placental function tests in the antepartum Identification of growth retardation.