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 .
Postpartum thyroid dysfunction in pregnant thyroid peroxidase antibody-positive women living in an area with mild to moderate iodine deficiency: is iodine supplementation safe?
In moderately iodine-deficient , pregnant , thyroid peroxidase antibody (TPO-Ab)-positive women the role of iodine supplementation in the development of postpartum thyroid dysfunction ( PPTD ) was studied in a placebo-controlled , r and omized , double blind trial . Screening for TPO-Ab was performed in early pregnancy in a population of healthy pregnant Danish women with no previous diagnosed thyroid disease ( prevalence , 117 of 1,284 ; 9.1 % ) . The participants were r and omized , stratified according to TPO-Ab level , to three groups . All participants received a daily vitamin and mineral tablet with 150 microg iodine or no iodine . The + /+ group received iodine during pregnancy and the postpartum period , the + /- group received iodine during pregnancy only , and the -/- group received no iodine supplementation . A total of 66 TPO-Ab positive women were followed , and in the postpartum period sera were collected at 8-week interval for biochemical evaluation of thyroid function and antibody level . Compliance was evaluated by 24-h urinary iodine measurements . PPTD developed in 55 % of the participants . In 67 % of the cases abnormal TSH was accompanied by abnormalities in thyroid hormones , whereas 33 % had abnormal serum TSH only . There was no statistically significant difference in the frequency of PPTD in the three groups : + /+ group , 59 % ( 95 % confidence interval , 36 - 79 % ) ; + /- group , 60 % ( 36 - 81 % ) ; and -/- group , 46 % ( 26 - 67 % ) . There were also no differences in the severity of the PPTD , as evaluated by duration and grade of deviation of TSH and thyroid hormones from normality . The occurrence , severity , and type of PPTD predominantly depended on the TPO-Ab level : TPO-Ab below 200 U/L at screening , 35 % developed PPTD ; TPO-Ab of 200 - 900 U/L , 54 % ; and TPO-Ab above 900 U/L , 75 % developed PPTD . Women with low levels of antibodies predominantly remained euthyroid or had hyperthyroidism only , whereas women with high antibody levels had hyperthyroidism followed by hypothyroidism or hypothyroidism only . We conclude that iodine supplementation ( 150 microg ) during pregnancy and the postpartum period to TPO-Ab-positive women living in an area with mild to moderate iodine deficiency did not induce or worsen PPTD . The study confirmed that screening for TPO-Ab in early pregnancy can predict women at high risk for development of PPTD
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 .