Inadequate iodine nutrition of pregnant women from Extremadura (Spain)

Abstract

[Objective]: To evaluate the iodine nutrition of the pregnant women of the Spanish Autonomous Community Extremadura. There are approximately 10,000 births per year in Extremadura, which historically contains areas with endemic goiter (Las Hurdes). DESIGN: Population study in which a representative sample of pregnant women of the general population was analyzed, along with another sample of pregnant women from traditionally goitrogenic areas. With the collaboration of selected health centers, an additional sample of blood and urine was obtained within the primary health care pregnancy-monitoring program; these samples were sent to a single central laboratory. [Methods]: Biochemistry: determination of iodine and creatinine in urine, and serum concentrations of thyroxine, free thyroxine, tri-iodothyronine, TSH, thyroglobulin, and two anti-thyroid antibodies. Each parameter was measured by means of a single specific RIA. RESULTS: Changes between the first trimester and later stages of pregnancy of all biochemical variables studied corresponded with those described for other European areas with a comparable iodine nutrition. Using the urinary iodine concentration value as an indicator of iodine ingestion, it was found that in the first trimester of pregnancy six out of ten women from Extremadura ingested less than the currently recommended amount (250 microg I/day), and approximately three out of ten of these women ingested less than half of this amount. [Conclusions]: It is imperative to implement in all Extremadura the generalized and controlled use of complements that contain 200-250 microg I/day throughout pregnancy and, if possible, before.