Thyroid hormones are vital for normal fetal growth and development during the first trimester of pregnancy. The thyroid gland is situated in the front of your neck that releases hormones, control metabolism, the heart and nervous system, manage weight, body temperature, and other vital processes in the system. Hypothyroidism and hyperthyroidism are relatively common in pregnancy, hence thyroid levels should be evaluated before and throughout the pregnancy.

Thyroid hormones are mainly required to guarantee the healthy development of the fetal brain and nervous system during the first three months of pregnancy, as the baby totally relies upon the mother’s hormones which are given via the placenta. At about 12 weeks, the thyroid gland in the fetus will start to produce its own thyroid hormones.
Doctor testing for thyroid

Women with pre-existing thyroid problems should get more intense medical care to regulate these conditions while they are pregnant. In very rare cases, pregnancy may result in symptoms similar to hyperthyroidism, such as palpitations, weight loss, or continuous vomiting, in such cases, contact your gynaecologist immediately.

Also Read: Planning For A Pregnancy? Watch Out For These Symptoms In Early Stages

If left untreated thyroid problems may lead to premature birth, preeclampsia, miscarriage, and low birth weight. Hence it is important to talk to your gynaecologist if you have had a history of hypothyroidism or hyperthyroidism, so your health status can be evaluated before and during pregnancy and ensure that your medications are properly modified if required.

Symptoms of Thyroid Problems in Pregnancy

Hyperthyroidism (Overactive Thyroid)

Usually, symptoms of hyperthyroidism may be quite similar to those of pregnancy like increased heart rate, sensitivity to hot climates, and tiredness. Other symptoms include:

  • Irregular heartbeat
  • Intensified nervousness
  • Severe nausea or vomiting
  • Poor sleep schedule
  • Weight loss or low weight gain beyond that expected of a pregnancy

Hypothyroidism (Underactive Thyroid)

Symptoms of hypothyroidism like exhaustion and weight gain may be easily mistaken for normal symptoms of pregnancy. Other symptoms may include:

  • Constipation
  • Difficulty concentrating
  • Sensitivity to cold temperatures
  • Muscle cramps

Also Read: Hypothyroidism Diet: Here’s Is What You Should Eat And Avoid To Manage This Disorder

Causes of Thyroid Problems in Pregnancy

Hyperthyroidism during pregnancy is caused by the autoimmune disorder Grave’s disease, where the system makes an antibody (a protein produced by the body when it mistakes it as virus or bacteria) called thyroid-stimulating immunoglobulin (TSI) that causes the thyroid gland to overreact and produce excess thyroid hormone.

In a person who has undergone radioactive iodine treatment or surgery to remove the thyroid, the system can still produce a TSI antibody. If these levels increase very high, TSI will travel via the blood to the developing fetus and starts producing more hormone than it requires. So, it is important for pregnant women to monitor thyroid levels regularly to ensure safe and normal pregnancy.

Hypothyroidism is caused by the autoimmune disorder known as Hashimoto’s thyroiditis. Where the system mistakenly attacks the cells of the thyroid gland, leaving the thyroid gland without enough cells and enzymes to make adequate hormones to meet the body’s requirements.

Diagnosis

The healthcare provider would completely evaluate the patient based on symptoms and recommend certain blood works to measure the levels of thyroid-stimulating hormone (TSH) and thyroid hormones T4 and T3 to determine thyroid disorders in pregnancy.

Treatment

The doctor usually prescribes antithyroid medication that hinders the production of thyroid hormones to treat hyperthyroidism. In a very rare situation, when women do not respond to medications or exhibit side effects from the therapies then surgery may be required to remove part of the thyroid. Also, hyperthyroidism may get aggravated during the first 3 months post-delivery and you would be monitored regularly and may also need to increase the dose of drugs.

The main course of treatment for hypothyroidism is a hormone called levothyroxine which mimics the action of the hormone T4 produced by the thyroid gland. The healthcare provider will titrate the dose of medicine at diagnosis of pregnancy and will continue to evaluate thyroid function tests every 4-6 weeks during pregnancy. Also, it is important to inform your doctor if you have hypothyroidism and are taking medication as soon as you know about your pregnancy, so that the dose of medication may be increased accordingly to meet the increasing need for thyroid hormone required during pregnancy. Moreover, iron and calcium supplements taken by you during pregnancy may impede the absorption of thyroid hormone in the system and prenatal vitamin should not be taken within 3-4 hours of taking thyroid hormone tablets.