TTTS

CLINICAL PROBLEM: Twin-to-twin transfusion syndrome (TTTS) increases perinatal morbidity and mortality for 10 to 15% of monochorionic (MC) gestations. PATHOPHYSIOLOGY: MC gestations are at risk due to the angioarchitecture of the shared placenta, with anastomoses of varying type, size, and quantity. TTTS results from progression of a chronic perfusion imbalance across unbalanced placental anastomoses, typically arising between 15 and 26 weeks gestation. The resulting abnormal fetal blood volume levels and compensatory physiological responses lead to an increased risk for fetal death, end-organ damage, and preterm birth...