A rare anomaly in twin pregnancy--acardiac twin.

Twin reversed arterial perfusion syndrome is the extreme manifestation of twin to twin transfusion syndrome. The pathogenesis is thought to be reversed arterial transfusion. Acardiac foetus grossly features severe reduction anomalies particularly of the upper body. Although the acardiac twin is nonviable, it can cause severe obstetric, foetal and maternal complications. Here, one such case of acardiac twin in reported.