For prevention of Rh(D) haemolytic disease of the foetus or neonate administration of a sufficient amount of specific anti-Rh(D) immunoglobulin is necessary. To this end the amount of foetal erythrocytes in the maternal circulation must be assessed. For this several methods are used. In the present study the authors tested blood samples of Rh(D) negative women after delivery of a Rh(D) positive foetus, women during the third trimester of gestation, after amniocentesis and after abortion. The authors used the gel agglutination technique, some of the samples were moreover examined also by the Kleihauer and Betke test. 51 samples from a total 443 were positive in the agglutination test. 3 samples from a total of 72 were positive in the Kleihaueretke test. Only in one instance positivity was confirmed in both tests. Ten times significant foetomaternal haemorrhage was confirmed ( ł 0.4 % foetal erythrocytes). The test of gel agglutination is simple and not time consuming, suitable for routine screening. However, its basic disadvantage is, that when the recommended procedures are respected, it does not make quantification of significant haemorrhage possible and thus of the correct dose of anti-D immunoglobulin for prevention of alloimmunization of the patients.

        Key words: foetomaternal haemorrhage, prevention of Rh(D) immunization, gel agglutination techni- que, Kleihauer-Betke test