The Acid-base Equilibrium in Abnormal Pregnancy

In previous papers (9, 14) we have discussed the changes that occur in the acid-base equilibrium of serum of normal women during pregnancy. In brief, these changes are reduction of the serum carbon dioxide content and serum proteins, accompanied by a comparable reduction of total base. These findings have been confirmed by Stander, Eastman, Harrison, and Cadden (21). The reduction of serum proteins appeared to be at the expense of the albumin fraction (5, 9, 17). Stander et al. (21) reported a normal hydrogen ion concentration and this has been confirmed by us (9). Thus the reduction of the carbon dioxide content of the serum, which has long been known to occur during the course of normal pregnancy, is associated with a diminished total base and not an accumulation of other “acids.” The explanation of these abnormal findings remains obscure and it was felt that a study of abnormal pregnancy might contribute not only to the solution of the pathogenesis of the toxemias themselves but also to the explanation of the acid-base disturbances in normal pregnancy. During the course of pregnancy there may occur one of a group of disorders, loosely termed the toxemias of pregnancy. Because of their obscure etiology as well as clinical diversity, the classification of the toxemias has been difficult and confused. The numer-