Management of twin-twin transfusion syndrome in monochorionic twin gestations

Abstract

Twin-twin transfusion syndrome is one of the most serious complications of monochorionic multiple gestations. Its etiology is due to a chronic blood transfusion from de donor twin to the recipient twin through the vascular anastomoses between the placental territories of both fetuses. The characteristic clinical presentation appears in both donor and recipient fetuses, as a direct consequence of altered volemia in each one. Polyhydramnios related to polyuria resulting from a state of constant hypervolemia is observed in the recipient twin, finally evolving into congestive heart failure. The clinical presentation in the donor twin is reversed and characterized by oligoamnios, oliguria, retarded intrauterine growth and hypovolemia, with untreated mortality rates ranging 80-100 % of all cases, which may vary depending on the severity of the transfusion. The diagnosis is based on exhaustive echographic examination of both fetuses to make an early diagnosis and correct staging, since the prognosis depends very much on early action. The treatment of choice is fetoscopic laser coagulation of vascular anastomoses between 18 and 26 weeks of gestation. The prognosis is variable, depending on the availability of fetal therapy and the gestational age at diagnosis, being prognosis generally very poor without an effective treatment.