Abnormal antenatal ultrasound findings and subsequent handicap.

The modern ultrasound technique in its various modes, real-time B-mode, M-mode, continuous and pulsed wave Doppler ultrasound, makes it possible to study in detail the fetal anatomy and function in utero. Fetometry allows for the evaluation of fetal size and growth and for detecting growth-retarded or macrosomic fetuses. Ultrasound seems, at present, to be the best method available in the detection of the growth-retarded fetus who is at risk of developing perinatal complications and subsequent handicap. Ultrasound can also be used when fetal growth retardation is suspected on clinical grounds. An absolute prerequisite for the proper use of ultrasound fetometry is the estimation of gestational age in early pregnancy. The high resolution of modern ultrasound scanners allows the antenatal detection of even minor fetal structural abnormalities. When lethal malformations are detected early in pregnancy, selective termination of pregnancy can be considered. Fetal abnormality detected in late pregnancy allows for optimal timing and mode of delivery leading to improved management and outcome, thus lowering the risks of subsequent handicap. Ultrasound examination of the extrafetal structures, e.g. umbilical cord, placenta and amniotic fluid volume, may add valuable clinical information. The finding of severe oligohydramnios is associated with increased perinatal mortality and morbidity. Fetal circulation can be evaluated by using the combination of real-time and pulsed Doppler ultrasound or, alternatively, by employing continuous wave Doppler ultrasound alone. Pathological changes in the blood velocity waveforms recorded from the fetal and umbilical arteries may signify very early signs of fetal hypoxia. The method has the potential of becoming a useful clinical method for fetal surveillance. The guidelines for a proper application in the perinatal medicine of the Doppler method have, however, not yet been established. In fetuses with cardiac arrhythmia and/or cardiac malformation, the Doppler investigation of the fetal circulation can be used to evaluate the haemodynamic alterations and, in cases of intrauterine treatment, to supervise and monitor the therapeutic effects. Fetal motor function can be followed and quantified with real-time ultrasound. Abnormal motor activity might indicate bad perinatal outcome. The predictive capacity of the test is increased when several variables are combined (e.g. the fetal biophysical profile score).(ABSTRACT TRUNCATED AT 400 WORDS)