REVIEW ER 'S CONCLUSIONS Iodine supplementation in a population with high levels of endemic cretinism results in an important reduction in the incidence of the condition with no apparent adverse effects
BACKGROUND Iodine deficiency is the leading preventable cause of intellectual impairment in the world .
Although iodine supplementation is generally considered to be safe , there is a possibility of high doses of iodine suppressing maternal thyroid function .
OBJECTIVES The objective of this review was to assess the effects of iodine supplementation before or during pregnancy in areas of iodine deficiency .
The effects of iodoprophylaxis on thyroid size during pregnancy.
Thyroid gl and size was ultrasonographically determined in 35 pregnant women who live in an area with moderate iodine deficiency .  Iodide salt was administered to group A ( n = 17 ) , whereas group B ( n = 18 ) was used as a control . Each group was tested for thyroid-stimulating hormone serum levels , iodine excretion , and thyroid volume . In both groups thyroid-stimulating hormone levels were similar and did not change throughout pregnancy . The iodine excretion at the third trimester in the treated group was significantly ( p less than 0.01 ) higher than that of group B ( 100.0 + /- 39.0 versus 50.0 + /- 37.0 micrograms iodine per 24 hours , respectively ) . Initially , thyroid volume did not differ between the two groups . At the end of pregnancy , no difference was found in thyroid size in group A , whereas in the untreated women it increased significantly ( p less than 0.0001 ) with a mean increase of 1.6 + /- 0.6 ml ( 16.2 % + /- 6.0 % ) . These results show that the increased thyroid size in the control group was mainly a result of relative iodine deficiency and that iodoprophylaxis should be warranted even in areas with moderate iodine deficiency to prevent the increase in thyroid size and , probably , to avoid the risk of maternal and fetal hypothyroidism
REVIEW ER 'S CONCLUSIONS Iodine supplementation in a population with high levels of endemic cretinism results in an important reduction in the incidence of the condition with no apparent adverse effects
BACKGROUND Iodine deficiency is the leading preventable cause of intellectual impairment in the world .
Although iodine supplementation is generally considered to be safe , there is a possibility of high doses of iodine suppressing maternal thyroid function .
OBJECTIVES The objective of this review was to assess the effects of iodine supplementation before or during pregnancy in areas of iodine deficiency .