[Indications and results of antenatal karyotyping (author's transl)]

From 1972 to 1975, 64 genetic amniocenteses and 72 cell cultures from amniotic fluids were done for antenatal karyotyping. In 3 cases a therapeutic abortion for genetic indication was carried out. The indications for antenatal karyotyping, the technique and complications of genetic amniocentesis in early pregnancy and the methods of cell cultures of amniotic fluid are discussed. A compilation of the results of 1918 antenatal karyotypings reported in the literature shows the following probability for the presence of an unbalanced chromosomal anomaly in the fetus: in mothers over age 40 4.25%, in mothers age 35-39, 1.45%, in cases with trisomy-21 in a previous sibling 0.73%, in cases with balanced chromosomal anomalies in the parents, 15.2%. In the next few years an increase of antenatal karyotyping in the different risk groups can be expected. In the individual case the indication for genetic amniocentesis must be balanced against the risk of complications.