[Monochorionic twin pregnancy and the following problems].

Monochorionic twin pregnancies have an increased risk of intrauterine and postnatal complications because of the present placental vascular anastomoses. The main problems are the development of twin-to-twin transfusion syndrome,selective intrauterine growth restriction, monoamniotic twins and single intrauterine death on the one hand and congenital abnormalities like twin reversed-arterial perfusion and conjoined twins on the other hand. Fetoscopic laser therapy with selective coagulation of placental intertwin anastomoses is the best option in the treatment of twin-to-twin transfusion syndrome. The risk of preterm delivery, cerebral injury and abnormalities of long-term neurodevelopmental outcome are increased. Perinatal management of monochorionic twin pregnancies should be performed in specialized tertiar centers.