Acardiac acephalic monster extremely larger than its co-twin. A case report.

The acardiac monster represents a rare but one of the severest congenital anomalies which occur only in multiple pregnancy. The affected fetus is sustained by a parasitic anastomosis to the umbilical blood vessels of the normal fetus. We report an interesting case of a macrosomic acardiac acephalic fetus weighing 4.5-fold of another variable donor fetus (approximately 6 kg) in a twin pregnancy.