[Comparison between clinical information capability of increased alpha-fetoprotein values in amniotic fluid and in maternal serum (author's transl)].

Tests were applied to 118 out of 1,534 patients in a programme for alpha-fetoprotein analysis to compare values recorded from amniotic fluid with those obtained from maternal serum. The tests were part of a prenatal diagnosis scheme by which to rule genetic defects. Six clearly increased alpha-fetoprotein values which were indicators to malformations and admixture of fetal blood were recorded from amniotic fluid by means of Mancini's technique. No falsely negative findings were recordable. Only two values were increased in maternal serum, among them one falsely positive result with no malformation at all. The conclusion drawn from the above findings is that in the context of prenatal diagnosis of malformation the most reliable values are obtainable from determination of alpha-fetoprotein in amniotic fluid. Maternal serum tests may be recommended for screening for neural tube defects, with due reference to be made to upper limit values.