Twin-to-twin transfusion syndrome -TTTS is observed in 10-15% of monochorionic twin pregnancies. The pathogenesis of the syndrome is still unknown, and the mortality reaches 80-90% if not treated. There are two invasive treatment options of TTTS: Fetoscopic laser coagulation of the placental anastomoses and serial amniodrainages. Endoscopic laser coagulation of anastomoses is a more effective first-line treatment than serial amnioreduction for severe TTTS. The rate of major neurologic complications is higher in amnioreduction group, than in Fetoscopic group.