Acardiac twin: an unusual case report.

Acardiac twinning is a rare anomaly .75% of cases occurring in monzygotic triplet pregnancies and the rest in monozygotic twins. We report an antenatally undiagnosed case of acardius amorphous. The condition results from abnormal placental vascular anastomoses termed as twin reversed arterial perfusion (TRAP) theory. Early sonographic prenatal diagnosis improves the survival of the normal twin called the pump twin.