Prenatal detection of heart defects as an indication for chromosome analysis.

Chromosome investigations were carried out in 588 fetuses with prenatally diagnosed growth retardation and/or congenital malformations. Out of these cases 116 (19.7%) revealed a chromosome disorder. Among the prenatally diagnosed malformations heart defects were detected in 102 fetuses (17.3%) and were therefore one of the most common abnormalities. Within this group of prenatally diagnosed heart defects 41 fetuses (40.2%) had a chromosome disorder, with trisomy 18 and 21 as the most common syndromes. The results of our study demonstrate that heart defects which can be recognized prenatally by ultrasound are caused in about 40% of the cases by a chromosome aberration and that they are therefore always an indication for fetal karyotyping.