Iodine is one of minerals of major importance throughout your pregnancy, however many women are unaware of the vital role iodine plays especially in relation to the development of the baby.
The iodine status of Australian women has been described as inadequate, and at present the majority of pregnant women have been described as having mild or moderate iodine deficiency. This contributes also to the mild iodine deficiency that has been found across most children.
Iodine is essential for the production of thyroid hormones. Approximately 75% of the body’s iodine is contained within the thyroid gland, a small gland that sits in your neck. The thyroid gland then uses your stores of iodine to help produce thyroid hormones, that are needed for a range of different functions within the body. In addition, during pregnancy these hormones are used for the development of your baby’s brain and nervous system, as well as the early growth and development of most organs right up until their first two years of life.
What can an iodine deficiency mean for my pregnancy?
Iodine deficiency can cause the following:
- Fertility problems – You may find it more difficult to fall pregnant if your thyroid hormone levels are low.
- Miscarriage – If deficiency is severe in early gestation there is an increased risk that you may lose your pregnancy.
- Premature labour – You will have an increased risk of going into labour earlier than your due date, which can lead to illness and respiratory problems in your baby.
- Impaired fetal development – In cases of severe iodine deficiency, there may be problems with the development of your baby’s brain and other neurological organs. These changes are generally irreversible.
- Impaired neuropsychological functioning of your baby – Your child may suffer from mental retardation, impaired psychomotor development, intellectual deficit and reduced IQ, as well as have learning problems. These can continue into adulthood and have serious impact on their mental capacity in adult life.
How much iodine do I need during my pregnancy?
During the first and second trimesters of pregnancy your growing baby is completely dependent on your own stores of thyroxine hormone for their requirements. By the time you reach the third trimester, your baby’s thyroid gland is developed and is therefore able to produce their own thyroid hormones, however will still require iodine from your resources. This continues throughout the breastfeeding period, unless formula milk is used. In summary during pregnancy your iodine requirements double, as shown in this table. Women that suffer from pre-existing thyroid conditions will require more.
Recommendations for iodine consumption, as supported by the National Health and Medical Research Council of Australia, state:
- Iodine supplements are recommended for all pregnant and breastfeeding women.
- One supplement per day will provide you with 150mcg of iodine.
- You should begin taking these when you are planning to fall pregnant or immediately after finding out you are pregnant, and continue throughout the full duration of your pregnancy and breastfeeding period.
Iodine supplement tablets are available widely at chemists or supermarkets and are safe for use in pregnancy and breastfeeding. There is no risk of over-consumption of iodine as the body will naturally excrete any excess.
Where can I find iodine in my diet?
In 2009 it became compulsory in Australia that all bread be fortified with iodine through the use of iodized salt in order to improve our iodine levels. This includes all bread products such as buns and loaves except any product labeled as organic. However given that pregnant women have increased requirements, bread alone will not achieve the recommended iodine intake.
Food sources that contain iodine are limited and are highly variable in iodine content, depending on season and method of processing, which is why supplements are the preferred source. Foods that do contain iodine include fortified bread, eggs, iodized salt, canned salmon, dairy and some seafood. Other natural iodine supplements that are available such as kelp and seaweed based products are not recommended in pregnancy as they can be contaminated with heavy metals such as mercury which can be dangerous during pregnancy.