Vasa previa is a condition in which one or more fetal blood vessels run through the amniotic membranes and cross or run near the external orifice of the uterus. Rupture of membranes can lead to tearing of these vessels and cause acute fetal exsanguination. In monochorionic twin (MC) pregnancies, acute exsanguination in one twin can lead to severe complications in the co-twin due to the presence of inter-twin placental vascular connections. We report a MC pair with severe perinatal asphyxia due to acute exsanguination after prenatally undetected ruptured vasa previa. This resulted in severe hemorrhagic shock in both twins with double fatal outcome. Antenatal detection of vasa previa is of paramount importance to prevent severe morbidity and mortality, especially in MCs. A review of the literature is presented.
Keywords: Acute twin-twin transfusion syndrome, double fatal outcome; MC twin pregnancies monochorionic twins, vasa previa.