Plasma protein fractions in normal pregnancy, labor, and puerperium

Abstract

A cumulative study has been made of the various protein fractions in the blood plasma of normal nonpregnant, pregnant, parturient, and puerperal women, using the Wu method of analysis. It was hoped to relate the changes in some one fraction, globulin or fibrin particularly, with the changes in watery dilution of the blood during the reproductive cycle. The curve developed for fibrin corresponds rather closely with that for plasma volume percentage, and it is suggested that perhaps the dilution of the plasma may be directly related to the increase of fibrin, although it is thought that other factors may have a rôle. The cause of the fibrin increase is admitted to be unknown, but not much consideration is given to the idea that it may be the result of a mild gestational injury to the liver. The accurate relationship between the rise in fibrin and the increased sedimentation rate of the blood cells, in the absence of any similar changes in the globulin fraction, leads us to agree with those who believe that the latter is the result of the former, the increased agglutination of the red cells into rouleaux being an intermediate and necessary stage for the increase in sinking velocity. There is a rise of globulin on the third day after delivery which may be directly associated with the onset of milk secretion.