The 'TRAP' sequence--life threatening consequences to the pump twin.

The acardius foetal malformation is a rare abnormality occurring in monozygotic multiple pregnancies. This is a case report of a pair of twins with the "twin reversed arterial perfusion (TRAP)" sequence and its complications. The recipient twin was born acardius acephalus. The pump twin had problems of prematurity, disseminated intravascular coagulation, sclerema and right ventricular hypertrophy. On follow-up at seven months he has failure to thrive, spastic quadriplegia and developmental delay. An awareness of the TRAP sequence may lead to better antenatal diagnosis and optimal management of the twin pregnancy.