The serum alkaline phosphatase of pregnancy

Abstract 1.1. Boyer's 6 observations on the occurrence of distinct alkaline phosphatase components in serum during pregnancy were confirmed with the use of a new technique. 2.2. The pregnancy phosphatase was detected during a population study because of its characteristic electrophoretic mobility in starch gel following incubation of serum with neuraminidase. The association with pregnancy was established by reference to birth records, and was confirmed by testing 20 sera obtained from mothers at the time of delivery, and also by demonstrating the presence of the unusual phosphatase during sequential pregnancies and its absence between the pregnancies. 3.3. The phosphatase was distinguished from another pregnancy-associated protein, namely, the alpha-2 globulin of pregnancy. 4.4. The role which the placenta may have in the induction of these proteins is discussed.