Thyroid diseases during pregnancy and foods to manage them
If you are expecting, you are probably aware of how different hormones can impact your body functions during this phase. And thyroid hormones, produced by the thyroid gland, deserve a special mention among these, as they affect everything from bone growth to metabolic rate to protein synthesis. Hence, thyroid diseases, which involve the thyroid gland, can interfere with a healthy pregnancy. In this article, we explore the common thyroid diseases that occur during pregnancy and how you can still ensure a healthy, normal pregnancy by eating the right foods.
More on the thyroid gland
The thyroid is a small, butterfly-shaped gland located in the front of your neck, which produces thyroid hormones. When the thyroid produces too much of these hormones, the condition is called hyperthyroidism. And when the thyroid produces very little of these hormones, it is known as hypothyroidism.
If you are ba ttling with hyperthyroidism or hypothyroidism during pregnancy, don’t worry, as you can still go on to have a successful birth, provided you get regular thyroid function tests done and take the prescribed medications.
Role of thyroid hormones during pregnancy
Thyroid hormones play a major role in the development of your baby’s brain and nervous system. In the first trimester, the thyroid hormones are transferred to the foetus through the placenta of the mother. By 12 weeks, a baby starts producing thyroid hormones on his own and is self-sufficient by around 18 to 20 weeks of pregnancy.
Now, human chorionic gonadotropin and oestrogen are the two hormones responsible for increased thyroid levels during pregnancy. In healthy women, the thyroid gland enlarges just slightly during pregnancy. Higher levels of thyroid hormones are usually hard to detect during pregnancy, but there are some symptoms of hyper and hypothyroidism that are easier to detect. A third type of thyroid disorder that might be seen after your baby is born is postpartum thyroiditis.
Types of thyroid disorders
- Hyperthyroidism in pregnancy: Some signs and symptoms of hyperthyroidism are as follows:
- Fast, irregular heartbeat
- Shaky hands
- Weight loss that is unexplained or failure to gain weight during pregnancy
The cause of hyperthyroidism during pregnancy is Grave's disease, which is an autoimmune disorder, in which the mother’s immune system produces antibodies that stimulate the thyroid gland to overproduce thyroid hormones. For some, Grave's disease starts during pregnancy and for others, who already have it, the disease worsens as the pregnancy progresses. But it again elevates the hormones after the baby is born. In rare cases, hyperthyroidism is also linked to hyperemesis gravidarum, which causes severe nausea and vomiting, resulting in weight loss and dehydration. In this case, high Hcg levels make the thyroid gland overactive, but this condition can be managed during the second half of the pregnancy.
Untreated hyperthyroidism can cause:
- Premature birth
- Low birth weight
- Preeclampsia, which causes high blood pressure in late pregnancy
- Thyroid storm, which is a sudden and severe worsening of symptoms
- Congestive heart failure
Rarely, Grave’s disease may also make the baby’s thyroid gland overactive. This overactive thyroid gland in a baby might lead to:
- Fast heart rate, which can result in heart failure
- Early closure of the soft spot in the baby’s skull
- Poor weight gain
The enlarged thyroid gland can also make it difficult for the baby to breathe.
- Hypothyroidism during pregnancy: Hypothyroidism is mainly caused by Hashimoto's disease, which is also an autoimmune disorder, where the body's antibodies attack the thyroid gland, causing inflammation, resulting in under-production of thyroid hormones.
Untreated hypothyroidism can lead to:
- Low birth weight
- Congestive heart failure
As thyroid hormones are needed for the development of your baby's brain and nervous system, hypothyroidism in the first trimester, when left untreated, can lead to low IQ and impaired development.
- Postpartum thyroiditis: This is an inflammation of the thyroid gland that mostly occurs in women with type 1 diabetes, and occurs during the first year after giving birth. Due to this condition, hyperthyroidism is first observed during the first three months, and then hypothyroidism is observed, because of the damage done to the thyroid. This can last up to one year after childbirth. For some women, this condition does not go away, and for some, only one phase is witnessed.
The hyperthyroidism phase in postpartum thyroiditis is accompanied by mild symptoms like irritability, trouble with sleeping, fast heartbeat, trouble dealing with heat, and tiredness. The hypothyroidism phase shows symptoms like trouble dealing with cold, trouble with focusing, tingling in hands, legs or feet, and dry skin.
Foods to avoid and eat for hyperthyroidism during pregnancy
In this condition, your thyroid gland produces the thyroid hormone in excess, and hence, iodine intake must be regulated. Some other foods that you should avoid are also given below:
- Foods containing excess iodine, like prawns, crabs, lobster, milk, cheese, and iodised salt should be avoided
- Avoid foods rich in nitrates, like lettuce, beets, cabbage, spinach, carrots, pumpkin, turnip and processed meats. These increase the absorption of iodine.
- These include barley, wheat, and malt.
- Soy foods like soy sauce, soy milk and tofu might interfere with medicines for hyperthyroidism, and should not be consumed.
The foods you can have are low-iodine options like egg whites, oats, potatoes, cruciferous veggies like cauliflower and broccoli, and iron-rich foods like lentils, nuts, poultry, and seeds. You should also include selenium sources in your diet, like mushrooms, rice and red meat in moderation. Zinc, which can keep your thyroid gland healthy, can be derived from mushrooms, cashews and pumpkin seeds. Calcium and vitamin D can be obtained from spinach, okra, cereals fortified with calcium and vitamin D, and fatty fishes. Healthy fats like oils from sunflower, coconut, olive, and flaxseed are also good choices.
Foods to avoid and eat for hypothyroidism during pregnancy
You will have to avoid foods that contain goitrogens and affect the thyroid gland, like:
- Soy foods like tofu, soy milk and soy sauce.
- Certain vegetables like cabbage, broccoli, spinach, cauliflower, etc.
- Fruits and starchy vegetables like sweet potatoes, strawberries, peaches, etc.
- Nuts and seeds like millets, pine nuts, peanuts, etc.
Cooking foods containing goitrogens can nullify their effect though. Other than these, all other foods can be consumed in a balanced manner.
Also, as mentioned before, hypothyroidism is caused by Hashimoto’s disease, which is linked to vitamin D deficiency as well. Hence, hypothyroidism can cause immense bone loss, and when coupled with a vitamin D deficiency, it can be severe. In such cases, supplementation might be necessary.
Selenium, essential for thyroid function, can be derived from red meat, rice and mushrooms. Also, include foods rich in vitamin B12, like rawas, orange, meat, and dairy, in your pregnancy diet. In hypothyroidism, consuming foods rich in iodine is important. So, go for dairy products, eggs, seafood, poultry, meat, and iodised salt.
Food to avoid and eat for postpartum thyroiditis
Avoid cold foods and drinks in this case, as they might lower your metabolism and weaken the immune system as well. Avoid junk foods as well. Also, since postpartum thyroiditis is characterized by both hyperthyroidism and hypothyroidism phases, the foods to avoid will depend on that. You can refer to the tips above for guidance.
As far as foods to eat are concerned, get enough calcium from dark green and leafy veggies as well as dairy products. Iron can be obtained from egg yolks, red meats, beans and spinach. Consume fruits rich in vitamin C along with them, like oranges and limes, to increase the iron absorption. Obtain zinc from seafood, eggs, and legumes, and load up on protein. Keep yourself well-hydrated too.
To conclude, suffering from thyroid problems during pregnancy doesn’t have to be the end of the world for you. With a few dietary changes and by taking prescribed medications, you can look forward to a healthy childbirth.