[Acute foeto-foetal transfusion syndrome--case report and review of the literature]

The perinatal morbidity and mortality risk in monochorionic twin pregnancies are 3-5-fold increased compared to those of dichorionic twin pregnancies. Partially, this is due to the higher rate of preterm delivery but also to the twin-to-twin transfusion syndrome (TTTS). Caused by unidirectional blood flow via placental anastomoses, the TTTS leads to weight differences of more than 20% between monochorial twins. The blood donor often shows oligohydramnios, whereas the recipient shows polyhydramnios. Lewi et al. demonstrated, in a study with 202 monochorionic twin pregnancies, a 9% rate of severe TTTS. The mortality of this complication is about 90% when untreated. In contrast to the chronic TTTS, little is known about the acute intrapartal one, which is characterised by anaemia and hypovolaemia of the donor and polyglobulia of the recipient without significant weight differences between the two. In most cases, anaemia occurred after normal delivery of the first twin. Still, there are no means or signs for early detection. We describe the case of a 30-year-old primigravida with a monochorionic diamniotic twin pregnancy. During pregnancy, no evidence of TTTS could be detected. At 37 + 1 weeks gestation labour was induced with prostaglandin-containing gel. Both foetuses showed cephalic presentation. The CTG of the first twin showed a conspicuous heart rate. After labour the first twin presented with anaemia and hypovolaemic shock, the APGAR was 2/7/8. The infant's haemoglobin was 13.7 g/dL. After delivery, the second twin with APGAR 10/10/10 showed a haemoglobin of 19.6 g/dL, which is in the upper normal range. Their birth weights differed by merely 10.4%. Acute TTTS is frequently characterised by anaemia and hypovolaemia of the second twin. In our case of a monochorionic twin delivery with acute TTTS the donor was born first. Early diagnosis and neonatal intervention is essential for reducing postnatal morbidity and mortality.