We report the prenatal diagnosis at 30 weeks of gestation of a del(8)(p21.3-->pter) in a growth-retarded fetus with an unbalanced atrioventricular septal defect (AVSD) and a hypoplastic right ventricle. This observation further confirms the association of AVSD with terminal deletions of chromosome 8p. Terminal deletions of chromosome 8p are more frequent than previously thought, but small terminal deletions can easily be overlooked. This observation illustrates that when an AVSD is diagnosed prenatally, special attention should be paid to distal chromosome 8p.