The thyroid gland is a small organ, but it has a big impact.
Note: It is particularly important to have your thyroid checked if you suffer from endometriosis or polycystic ovary syndrome (PCOS), as you are more likely to have problems with your thyroid if you have these conditions.2
Underactive thyroid and pregnancy
If left untreated, hypothyroidism in pregnancy can be very dangerous. Thyroid hormone is critical for brain development and can leave the baby at risk for learning and development problems.1
Treatment for hypothyroidism is the same regardless of whether a woman is pregnant or not. Taken orally, appropriate medication is recommended throughout pregnancy.1 Treatment for hypothyroidism during pregnancy is extremely important as it protects both the mother and baby from any potential future complications. Women with hypothyroidism prior to pregnancy will require a higher dose of the appropriate medication before becoming pregnant and more-frequent monitoring during pregnancy to make sure their medication dose is correct.1
Iodine deficiency and pregnancy
Iodine is vital for the production of thyroid hormones, and as your body does not produce iodine, it must be consumed as part of a healthy diet.3 Even a mild iodine shortage during pregnancy can have negative effects on the delivery and development of your baby, including your baby’s thyroid becoming underactive.1 It is therefore recommended that all pregnant and breastfeeding women take a nutritional supplement containing iodine every day.3 Women of childbearing age should have an average iodine intake of 150 micrograms per day, which should be increased to approximately 250 micrograms during pregnancy and to approximately 290 micrograms while breastfeeding.3
Overactive thyroid and pregnancy
An overactive thyroid (hyperthyroidism) in pregnant women is caused, in most cases, by Graves’ disease.1 Graves’ disease is an autoimmune disease that causes the thyroid gland to overproduce hormones, resulting in hyperthyroidism.
Failure to treat hyperthyroidism during pregnancy can increase the risk for stillbirth, premature birth and child deformities.1
The treatment for pregnant women with hyperthyroidism is sometimes different to that offered to other women, as some of the medications available can harm the unborn baby.1
Date of preparation: February 2022