Background: Bangladesh is an iodine deficient region and the government of Bangladesh, with assistance of UNICEF had initiated a universal salt iodinization program to provide iodized salt by the middle of 1994. Breast milk is the only source of iodine for exclusively breast-fed infants. Iodine deficiency and iodine excess both have bad impact on infant's health. Objectives: To assess the iodine status of lactating mothers and their breast-fed infants and to evaluate whether maternal iodine status reflects the iodine status of their breast-fed infants. Material and methods: This observational analytical study was carried out in the department of biochemistry, Bangabandhu Sheikh Mujib Medical University, Dhaka with active cooperation of Kumudini Women's Medical College Hospital, Mirzapur, Tangail involving fifty lactating mothers and their exclusively breast-fed infants. Early morning urine and breast milk samples were collected in dry and clean plastic containers free from any chemical contamination. Urinary iodine was used as an indicator for assessing iodine status. All statistical analysis was done by using SPSS (Statistical Program for Social Science) 12 version software package for windows. Results: The median (range) urinary iodine concentration of lactating mothers and their breast-fed infants were 225.25 µg/L (61.50-530.00) and 225.75µg/L (100.50-526.00). 96% (48) mothers had no biochemical iodine deficiency (UIE ≥100µg/L), only 4% (2) mothers had mild biochemical iodine deficiency (UIE, 50-99µg/L). There was no biochemical iodine deficiency of breast-fed infants. The median breast-milk iodine concentration was 157µg/L which was more than three times of recommended minimum concentration (50µg/L). Iodine in breast milk of lactating mothers was positively correlated with their urinary iodine excretion (P<0.01). Infant's urinary iodine was positively correlated with iodine concentration in breast milk (P<0.01) and also positively correlated with urinary iodine of lactating mothers (P < 0.01). Conclusion: Lactating mothers and their breast-fed infants in this study were iodine sufficient. Iodine status of exclusively breast-fed infants can be determined by the iodine status of their mothers.

The objective of the observational analytical study was to assess the iodine status of lactating  mothers and their breast-fed infants and to evaluate whether maternal iodine status reflects the  iodine  status  of  their  breast-fed  infants.  The  study  was  carried  out  in  the  department  of  Biochemistry, Bangabandhu Sheikh Mujib Medical University, Dhaka with active cooperation of  Kumudini Women’s Medical College Hospital, Mirzapur, Tangail involving fifty lactating mothers  and  their  exclusively  breast-fed  infants.  Early  morning  urine  and  breast  milk  samples  were  collected in dry and clean plastic container free from any chemical contamination. Urinary iodine  excretion (UIE) was used as indicator for assessing iodine status. The median (range) urinary  iodine  concentration  of  lactating  mothers  and  their  breast-fed  infants  were  225.3  ?g/L  (61.5-530.0)  and  225.8?g/L  (100.5-526.0),  respectively.  Of  the  mothers,  96%  (48)  had  no  biochemical  iodine  deficiency  (UIE  ?100?g/L),  only  4%  (2)  had  mild  biochemical  iodine  deficiency  (UIE, 50-99?g/L). There was no biochemical iodine  deficiency  of breast-fed infants.  The median breast-milk iodine concentration was 157?g/L which was more than three times of  recommended minimum concentration (50?g/L). Iodine in breast milk of lactating mothers was  positively  correlated  with  their  UIE  (p  <  0.01).  Infant’s  urinary  iodine was positively  correlated  with  iodine  concentration  in  breast  milk  (p  <  0.01)  and  also  positively  correlated  with  urinary  iodine of lactating mothers (p < 0.01). Lactating mothers and their breast-fed infants in this study  were iodine sufficient. Iodine status of exclusively breast-fed infants can be determined by the  iodine status of their mothers.Mediscope Vol. 2, No. 1: 2015, Pages 13-17

Iodine is a micronutrient, which is essential for the synthesis of thyroid hormones. Thyroid hormones play a major role in the development of different functional components in different stages of life. The relationship between iodine intake level of a population and occurrences of thyroid disorders U-shaped with an increase from both low and high iodine intake. Iodine deficiency disorders (IDDs) are a major health problem worldwide in all age groups, but infants, school children, and pregnant and lactating women are vulnerable. During pregnancy and lactation, the fetus and infants are sensitive to maternal iodine intake. Even mild iodine deficiency may lead to irreversible brain damage during this period. A main cause of IDDs of neonates and infants is maternal iodine deficiency. Universal salt iodization strategy has been initiated by the World Health Organization and United Nation International Children Emergency Fund by the year 1993 for correction and prevention of iodine deficiency. Excessive iodine causes hypothyroidism, iodine-induced hyperthyroidism and autoimmune thyroid diseases. Iodine deficiency and excessive iodine, both cause goiter. There are many indicators for assessing the IDDs, such as measurement of thyroid size by palpation or ultrasonography, serum thyroid stimulating hormone, and thyroglobulin but these are less sensitive, costly and sometimes interpretation is difficult. Urinary iodine concentration (UIC) is a well-accepted, cost-efficient, and easily obtainable indicator of iodine status. Since the majority of iodine absorbed by the body is excreted in the urine, it is considered a sensitive marker of current iodine intake and can reflect recent changes in iodine status. Iodine requirements are greatly increased during pregnancy and lactation, owing to metabolic changes. During intrauterine life, maternal iodine is the only source of iodine for a fetus. UIC determines the iodine status of pregnant and lactating women. Breast milk is the only source of iodine for exclusively breastfed neonates and infants. Breast milk iodine concentration can be determined by UIC. UIC predicts the adverse health consequences of excessive iodine intake such as goiter, hypothyroidism, and hyperthyroidism. This review presents that iodine status in different groups of a population can be determined by UIC which will be helpful in assessing the iodine status in a community, finding out the cause of thyroid disorders, to predict the risk of adverse health effects of iodine deficiency and excessive iodine, and in making plan for iodine supplementation.Mediscope Vol. 5, No. 2: Jul 2018, Page 30-35