What happens to T4 during iodine deficiency? What changes are imposed on maternal thyroid function by the fetus? What happens when a pregnant woman is iodine deficient? What effect does breast feeding have on iodine status? The answers to the above questions explain why iodine requirements are doubled from the very onset of pregnancy.
Thyroid hormone and iodine metabolism in pregnancy. experimental reasons for maintaining adequate iodine intake in pregnancy
 
  Key words
 
 
  
   Thyroxine
  
 
 
  
   Pregnancy
  
 
 
  
   Neurodevelopment
  
 
 
  
   Iodine deficiency
  
 
Iodine is an essential micronutrient without which the thyroid is unable to synthesize and secrete its two iodine-containing hormones, tetra-iodo- thyronine or thyroxine (T4) and 3’, 3, 5-tri-iodothyronine (T3), containing, respectively, 4 and 3 iodine atoms per molecule.
Both hormones are needed throughout life, with T4 being especially important for the development of the cerebral cortex as early as during the first trimester of pregnancy.
The need for adequate iodine intake is recognized among the Rights of the Child, since, after starvation, iodine deficiency is the most frequent nutritional cause worldwide of preventable <dis>mental retardation</dis>.
The present article discusses several questions: are T4 and T3 equivalent for the developing brain?
What happens to T4 during iodine deficiency?
What changes are imposed on maternal thyroid function by the fetus?
What happens when a pregnant woman is iodine deficient?
What effect does breast feeding have on iodine status?
The answers to the above questions explain why iodine requirements are doubled from the very onset of pregnancy.
Even in conditions of mild-moderate iodine deficiency, which still prevail throughout Spain, daily supplementation of at least 200 μg iodine is required to prevent mental retardation, starting, if possible, before the onset of pregnancy and continuing until the end of breast feeding.
Iodine is an essential micronutrient without which the thyroid is unable to synthesize and secrete its two iodine-containing hormones, tetra-iodo- thyronine or thyroxine (T4) and 3’, 3, 5-tri-iodothyronine (T3), containing, respectively, 4 and 3 iodine atoms per molecule.
Both hormones are needed throughout life, with T4 being especially important for the development of the cerebral cortex as early as during the first trimester of pregnancy.
The need for adequate iodine intake is recognized among the Rights of the Child, since, after starvation, iodine deficiency is the most frequent nutritional cause worldwide of preventable mental retardation.
The present article discusses several questions: are T4 and T3 equivalent for the developing brain?
What happens to T4 during iodine deficiency?
What changes are imposed on maternal thyroid function by the fetus?
What happens when a pregnant woman is iodine deficient?
What effect does breast feeding have on iodine status?
The answers to the above questions explain why iodine requirements are doubled from the very onset of pregnancy.
Even in conditions of mild-moderate iodine deficiency, which still prevail throughout Spain, daily supplementation of at least 200 μg iodine is required to prevent mental retardation, starting, if possible, before the onset of pregnancy and continuing until the end of breast feeding.
What happens to T4 during iodine deficiency? What changes are imposed on maternal thyroid function by the fetus? What happens when a pregnant woman is iodine deficient? What effect does breast feeding have on iodine status? The answers to the above questions explain why iodine requirements are doubled from the very onset of pregnancy.