Iodine nutrition of pregnant and lactating women in Hong Kong, where intake is of borderline sufficiency.
OBJECTIVE
To describe the iodine nutrition of pregnant and lactating women in Hong Kong, where intake is of borderline sufficiency.


METHODS
Review of cross-sectional and prospective studies.


METHODS
China, Hong Kong Special Administrative Region (SAR).


METHODS
Pregnant and lactating women.


RESULTS
Studies of pregnant women in Hong Kong SAR have revealed an increase in the urinary iodine (UI) concentration as pregnancy advances. A significant percentage of women had a sub-normal serum thyroid hormone concentration at full term. Although iodine is concentrated by the mammary gland, 19% of all mothers had low iodine concentrations in their breast milk. The moderate correlation between the concentrations of iodine in breast milk and urine suggests that an adequate maternal urinary iodine concentration cannot reliably indicate that an infant is getting enough iodine in breast milk. Therefore, some breast-fed infants may still be at risk of low iodine intake, and additional iodine supplements, other than salt iodisation, would be warranted in this population.


CONCLUSIONS
The currently recommended intake of iodine through universal salt iodisation may not be adequate for pregnant and lactating women, and supplementation during pregnancy and lactation should be further considered in light of the latest recommendations.
Kung
Annie W C
AW
Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China.
D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007455:Iodine / Q000008:administration & dosage / Q000172:deficiency* / Q000378:metabolism; D007774:Lactation / Q000378:metabolism / Q000502:physiology*; D039382:Maternal Nutritional Physiological Phenomena / Q000502:physiology*; D008895:Milk, Human / Q000737:chemistry; D009751:Nutritional Requirements; D009752:Nutritional Status; D011247:Pregnancy / Q000378:metabolism / Q000502:physiology*; D011446:Prospective Studies; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage
D017673:Sodium Chloride, Dietary; C034024:iodized salt; D007455:Iodine