[Prenatal diagnosis of trisomy-18-fetus of two women with chromosomal aberrations (author's transl)].

In two pregnant women a prenatal diagnosis was performed because of their advanced age. In both cases trisomy 18 was found. The mothers had chromosomal variations, not known until then. In one woman a structural aberrant chromosome No. 9 was found, the other woman had a gonosomal mosaic. In connection with the advanced maternal age these chromosomal findings possibly induced the trisomies in the children.