[Fetomaternal blood transfusion as a cause of severe obstetrical complications].

A Caesarean section was performed in a healthy secundipara of 26 years of age in the 39th week of gestation, because of severe alterations of foetal heart-rate patterns, signalling foetal distress. Amount and colour of the amniotic fluid appeared normal. A highly anaemic male infant was delivered (BW 2920 g, BL: 49.5 cm, RBC: 770 000/mm3, PVC: 11%). Since perinatal posttraumatic bleeding was excluded by the normal appearance of the umbilical cord and the placenta, transplacental foeto-maternal macrotransfusion was suggested immediately and diagnosis confirmed by demonstrating foetal red cells in the maternal circulation (79%) using a modified Kleihauer technique. Other causes of anaemia in the newborn such as haemolysis, coagulopathies and failure of red cell production were excluded later. Foetal erythrocytes can be demonstrated in the maternal circulation up to 80 days after delivery, provided the blood groups of mother and foetus are compatible. If this is not the case, there will be a rapid elimination of foetal red cells. Hence, it appears advisable to conduct a Kleihauer test directly if foeto-maternal transfusion is suspected. It may well be that some of the cases of unexplained foetal death are due to this phenomenon.