Acardiac twins

Three cases of twin pregnancy complicated by an acardiac twin are reported. This is a rare abnormality of twins. A vascular communication exists between the twins and the usually normal twin or so called 'pump' twin may develop cardiac failure as a result of perfusion of the abnormal twin. The acardiac twin is, generally, grossly abnormal with reduction anomalies, particularly of the upper part of the body, and gross oedema. Unless this abnormality is recognized the misdiagnosis of fetal death in utero may be made and the complications of the 'pump' twin may not be predicted. Three cases are presented with only one survivor.