Abnormal facial features and extremities in human trisomy syndromes: prenatal US appearance.

Twelve cases of fetal trisomy syndromes are reported in which prenatal sonographic findings were highly suggestive of the chromosomal abnormality. The abnormal appearance on the sonogram led to karyotype studies in ten fetuses and to appropriate obstetrical management. The sonographic abnormalities pertained to the extremities and face of the fetus.