Controlled trials on infant neurodevelopment were lacking ; gestational iodine supplementation reduced maternal thyroid volume and serum thyroglobulin and in some studies prevented a rise in serum thyroid-stimulating hormone .
Iodine supplementation improves some maternal thyroid indices and may benefit aspects of cognitive function in school-age children , even in marginally iodine-deficient areas .
BACKGROUND Although the detrimental effects of severe iodine deficiency are well recognised , the benefits of correcting mild-to-moderate iodine deficiency are uncertain .
OBJECTIVES We undertook a systematic review of the impact of iodine supplementation in population s with mild-to-moderate iodine deficiency .
Earliest prevention of endemic goiter by iodine supplementation during pregnancy.
During pregnancy complex changes of maternal thyroid function occur and they are influenced by the maternal iodine supply . It has been demonstrated that with decreasing iodine supply maternal goiter and hypothyroxinemia as well as fetal and neonatal hypothyroidism become more prevalent . Therefore iodine supplementation during pregnancy is now strongly recommended also in areas of moderate iodine deficiency . To monitor the success of iodine supplementation and its theoretical risk of increasing the frequency of thyroid autoantibodies , we have investigated the thyroid volume , thyroid function , urinary iodine excretion and antibodies to thyroid peroxidase at 10 - 12 weeks of gestation and postpartum in 38 mothers receiving 300 micrograms potassium iodide/day and in 70 mothers without iodine supplementation .  In all of their newborns thyroid volume was determined by ultrasound . The thyrotropin ( TSH ) levels and antibodies to thyroid peroxidase ( TPO-ab ) in the neonates were measured in dried blood spots on filter paper from their newborn screening . Urinary iodine excretion was increased significantly after iodine supplementation in mothers ( p < 0.001 ) and their newborns ( < 0.05 ) . No hypo- or hyperthyroidism was observed in the mothers or newborns . Interestingly , no difference of maternal thyroid volumes was observed between the two groups after pregnancy , but the volumes of the thyroid gl and s in newborns of mothers who received iodine were significantly ( p < 0.004 ) lower ( 0.7 + /- 0.4 ml ) than in the control group ( 1.5 + /- 1.1 ml ) . There was no change in the frequency of TPO-ab in either group after pregnancy . In four mothers transplacental passage of these antibodies was documented by positive measurement in the blood sample of the newborn . This study documents that iodine supplementation during pregnancy in an area of moderate iodine deficiency results in a lower size of neonatal thyroid volume and that this supplementation was not accompanied by an increase in the frequency of TPO-ab
Controlled trials on infant neurodevelopment were lacking ; gestational iodine supplementation reduced maternal thyroid volume and serum thyroglobulin and in some studies prevented a rise in serum thyroid-stimulating hormone .
Iodine supplementation improves some maternal thyroid indices and may benefit aspects of cognitive function in school-age children , even in marginally iodine-deficient areas .
BACKGROUND Although the detrimental effects of severe iodine deficiency are well recognised , the benefits of correcting mild-to-moderate iodine deficiency are uncertain .
OBJECTIVES We undertook a systematic review of the impact of iodine supplementation in population s with mild-to-moderate iodine deficiency .