[Alpha fetoprotein concentration in the amniotic fluid in normal pregnancy and in pregnancy complicated by fetal anomaly]

Abstract

The authors determined alpha-fetoprotein (AFP) concentration of amniotic fluid samples taken from 351 pregnancies in the 15-23. gestational weeks with the outcome of healthy infants with the use of radioimmunoassay. These values were compared to those of 255 pathological pregnancies, and the sensitivity and specificity of this diagnostic method based on amniotic fluid AFP assay were determined. It has been concluded that if the borderline value between normal and pathological cases is three times greater than median, the specificity of the method is 100%, its sensitivity is 98.5% in anencephaly (exencephaly), 75.0% in ADAM sequence, 70.4% in spina bifida and 55.5 in omphalocele (gastroschisis). Thus amniocentesis is advisable in cases where the risk of the above malformations is above the average and also when the possibility of the malformation cannot be excluded by non-invasive methods.