Rh antibodies; correlation with clinical findings.

T HE discovery of so-called ‘ ‘incomplete’ ‘ or ‘ ‘blocking’ ‘ antibodies and of thermostable agglutinins reacting in serum or albumin but not in saline has stimulated discussion and speculation on their relation to each other and to the previously known Rh agglutinins which react in saline solution, and more recently on their relation to the various forms of fetal erythroblastosis. The problem of the nature of the various forms of Rh antibody is one to be solved by immunologic and immuno-chemical methods. The second problem, of the respective role of the antibodies in the genesis of the different forms of the disease may be brought closer to solution by qualitative and quantitative study of antibodies during pregnancy and correlation with the condition of the newborn infant. This report aims to present the results of such a compatative investigation. It is based on a study of the titres of Rh antibodies (saline agglutinins, serumalbumin agglutinins, and blocking antibodies) in the blood of 73 mothers of rythroblastotic infants or fetuses. In most instances repeated blood samples were obtained at intervals during the pregnancy and after childbirth. In some cases tests extended over several years. Ten women had only one sample examined, but the average number for the remaining 63 women was 4. 5 samples. The technic of the various tests was essentially the same as described by Wiener and by Diamond. It was presented in detail in a chapter on blood groups in the forthcoming new edition of Kracke and Parker’s ‘ ‘Clinical Pathology. ‘ ‘