Michener, William M.

Normal values for the measurement of thyroidal function using the erythrocytic uptake of I131-labeled triiodothyronine and the thyroxine-binding capacity of the inter-alpha globulin were established. Paired maternal and cord blood samples collected at the time of delivery were studied with these methods. The erythrocytic uptake of labeled hormone was increased in cord blood as compared to maternal blood. Cord blood apparently binds exogenous triiodothyronine in a different manner than it does exogenous thyroxine. Whether this is a qualitative or quantitative difference was not shown in this study.