[Systematic antepartum fetal evaluation ("Safe"). A concept for diagnosis of fetal function in threatened hypoxia]

Abstract

Target: The significant aim of the study was to prove whether it makes sense to apply the classical approach of diagnostic procedures to the fetus.

Patients and methods: In a group of a total of 534 singleton pregnancies we examined the value of various biochemical and biophysical tests for detecting the risk of perinatal hypoxia. The sequence and combination of the most decisive tests was considered as well as the different approach within the observation period.

Results: Maternal laboratory findings like HPL and E3 were significantly less predictive of growth disturbance and compromise than any biophysical test. A small fetal abdomen detected by ultrasound ("observation") is up to now the earliest and most reliable predictor of foetal growth disturbance, followed by Doppler measurements of the uteroplacental circulation ("examination of the chronic respiratory function"). Examination of the foetal heart-circulatory function with pulsed Doppler and the foetal cardiac frequency (CTG) are the procedures of choice to determine the risk of perinatal hypoxia following pre-selection of foetuses, which are too old or too thin. In these patients, additional stress tests have neither medical nor a diagnostic advantage compared to the published function tests. Amongst the variety of biophysical tests, the Apgar score ("fetal Apgar score") was superior to all other tests in predicting prenatal or perinatal hypoxia and might even prevent invasive procedures.

Conclusion: The sequence from non-invasive biophysical tests, including the fetal Apgar score, to invasive procedures is recommended for screening and follow-up of preselected pregnancies at risk for perinatal hypoxia. This approach might be applied to other risk groups and will hopefully be supplemented by new noninvasive diagnostic tools allowing early prognosis and prevention of fetal and neonatal disease.