Twin to Twin Transfusion Syndrome

A disease of the placenta that affects identical twins during pregnancy when blood passes disproportionately from one twin to the other through connecting blood vessels in a shared placenta. One twin may receive too much blood overloading the cardiovascular system while the other receives too little, resulting in anemia. Without surgery or other forms of treatment, a large percentage of babies with this syndrome die in utero, are delivered prematurely or develop disabilities such as cerebral palsy. TTTS can occur in other multiples, e.g., triplets.