The author has developed a new, simple technic for the determination of the antiproteolytic power of blood serum. Experimental conditions such as the quality of the materials used and the temperature and duration of the reaction were strictly controlled. He measured antiproteolytic power in terms of the inhibitory action of 1 cc. of serum, as determined by the percentage of fibrin remaining unchanged during digestion with a proteolytic ferment. Proteolytic power was measured by the percentage increase of the fibrin broken down under the same conditions.
The method enabled the author to gather evidence in the female of a hitherto unknown proteolytic power of certain blood serums, but most of his data concern the antiproteolytic power of the blood serum in various obstetric and gynecologic conditions. Four hundred and sixteen observations were carried out in 314 female patients, of whom 168 were pregnant. More often than not only one determination