Urinary iodine excretion is low and serum thyroglobulin high in pregnant women in parts of Denmark

In the Randers area of Denmark urinary iodine excretion (which reflects iodine intake) was found to be much lower than recommended intake levels, both in women in late pregnancy [52(23-118) micrograms iodine/g creatinine, median, range, n = 20] and in non-pregnant controls [42(23-71), n = 20]. Serum thyroglobulin which is high in iodine deficiency was 32.5 micrograms/l (median) (range 10.5-78.0) in the control women and considerably higher in the pregnant women [67.0 micrograms/l (9.0-385)]. This increase was probably due to the extra iodine requirement of pregnancy which was not satisfied with an adequate increase in iodine intake. The results may suggest that pregnant women in this area should receive iodine supplementation and that a general program of iodine supplementation should be considered.