• The Rh Factor tn
Pregnancy Jack L.
Sales, '55
In this article the Rh factor is discussed from its discovery to its practical aspects in present day Obstetrics, stressing the diagnosis and management of its resulting complications. Discovery: older T HEattempted
medical literature contains occasional references to transference of blood from one person to another or from an animal to a man or woman. These experiments proved unsuccessful in most cases and the reason became apparent when Landsteiner in 1900 showed that there were differences in blood not only between species but within species. Landsteiner was able to divide human blood into three varieties and a short time later a fourth was added. It was also shown that if the agglutinogens A or B were not present in R.B.C. anti B or anti A agglutinins were present in the serum. The present system of classification is based on Landsteiner's original concept and four groups are recognized . Accurate blood grouping determination techniques which were practical slowly evolved and transfusion of blood became a recognized procedure about 1910. In 1911 variants of A (At and At) were discovered. In 1928 Landsteiner and Levine reported the presence of M. N and P substances in blood. Other cold agglutinins were demonstrated but the work between 1900 and 1940 did not reveal any antigen antibody "set-up" of practical importance in transfusion work other than the ABO groups. However, during this period of time several transfusion reactions resulted in fatalities. Some were due to administration of incompatible blood, contamination of blood, and poor technique but others could not be explained on this basis. Slowly it became apparent that these fatal reactions occurred in men and women previously transfused or in women who had been pregnant. These pregnancies were noted to end with stillborn delivery or infant death because of erythroblastosis. Early workers tried to link antigen antibody reactions due to placental passage of R.B.C. as a cause of eclampsia and erythroblastosis. In 1938 Darrow reviewed the literature and decided that an antigen NOVEMBER,
1954
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