Twin-to-twin transfusion syndrome
is a rare condition that occurs when blood moves from one identical twin (the Òdonor twinÓ) to the other (the Òrecipient twinÓ) while in the womb. The donor twin may be born smaller, with paleness, anemia, and dehydration. The recipient twin may be born larger, with redness, too much blood, and increased blood pressure, resulting in an increased risk for heart failure. Treatment may require repeated amniocentesis during pregnancy. Fetal laser surgery may be done to interrupt the flow of blood from one twin to the other. After birth, treatment depends on the infant's specific symptoms. The donor twin may need a blood transfusion to treat anemia. The recipient twin may need to have the volume of body fluid reduced. This may involve an exchange transfusion. Medications may be given to treat heart failure in the recipient twin. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.