Sonographic diagnosis of fetal coarctation of the aorta at 14-16 weeks of gestation.

The prenatal sonographic diagnosis of coarctation of the aorta is difficult. The objective of this study was to present a simple and reliable marker of this anomaly in early pregnancy. In fetuses with coarctation of aorta who were scanned at 14-16 weeks' gestation, a significant discrepancy was observed between a large ductus arteriosus and a smaller aorta at their point of connection. This difference between the sizes of the vessels probably reflects the reduced blood flow through the aorta and the compensatory increase in blood flow through the right outflow tract in cases of coarctation of the aorta.