The manner in which laboratory experiments were correlated with clinical data and the importance of the Rh factor in relation to the causation of erythroblastosis and of certain reactions to intragroup transfusions was established is one of the most interesting stories in recent medical literature. The short time that has elapsed since the Rh factor was first described has been sufficient to permit numerous investigations, and over one hundred papers on various phases of this subject have already been published. In common with many new discoveries its importance may be currently overemphasized, and the ultimate place the Rh factor will take in medical thought and practice cannot yet be foretold. There are numerous problems still to be solved, but in the following pages an attempt will be made to summarize the available information that exists at present.
Incompatible Blood as a Cause of Fetal and Maternal Morbidity.—Some