Accession Number : AD0618509

Title :   IODINE METABOLISM DURING HUMAN PREGNANCY IN AN AREA OF IODINE ABUNDANCE,

Corporate Author : WASHINGTON UNIV SEATTLE

Personal Author(s) : Dowling,J. Thomas ; Appleton,William G. ; Nicoloff,John T.

Report Date : 1964

Pagination or Media Count : 29

Abstract : A significant proportion of I132 as iodide leaves the circulation of pregnant women into a compartment other than thyroid or urine, presumably the conceptus. The compartment is obliterated by sodium thiocyanate, indicating an active transport mechanism. Thyroid and renal clearances of I132 are increased, the former to a proportionately greater degree than the latter, late in pregnancy. The net daily turnover of thyroxine iodine expressed in terms of body surface area is not increased by pregnancy. In the geographic area of the study, urinary iodine excretion and plasma iodide concentrations are higher, while thyroid iodide clearances are lower than in many locales. The data imply that a relative deficiency of iodide induced by hemodynamic changes and by the growing conceptus and its turnover of organic iodide contribute to the apparent hyperfunction of the thyroid during normal human pregnancy. (Author)

Descriptors :   (*PREGNANCY, IODINE), (*IODINE, METABOLISM), THYROXINE, EXCRETION, URINE, BLOOD PLASMA, EMBRYOS, SODIUM COMPOUNDS, THIOCYANATES

Distribution Statement : APPROVED FOR PUBLIC RELEASE