Hyperthyroidism And Pregnancy Complications

Pregnancy is a life event. It is a period of many transformations, including physical and mental changes. Even in an uncomplicated pregnancy, these changes can adversely affect a pregnant woman’s quality of life.

In a women’s life, pregnancy is like the second phase of life, as a fetus starts to develop inside a mother’s womb. At the same time, the mother’s life also changes along with it. A mother’s body not only shifts through hormonal changes but also affects her mental state. That’s why it is said that during pregnancy, a mother takes a second birth along with the baby. In this process, within each trimester, numerous changes occur till the final stage of pregnancy. A woman in her life experiences many hormonal changes from puberty to menstruation to pregnancy to menopause. In her lifetime, she undergoes several periods of hormonal imbalance.

There are many hormonal imbalances in a woman; one among them is the thyroid.

The thyroid is a disease that can affect anyone at any age but is most common among females than males. It is a disease that causes distress and affects the thyroid gland. It is a small organ which is located in front of the neck. It is shaped like a butterfly. The thyroid gland creates some hormones which help and control many essential functions of our body. Thyroid hormones control how our body is using energy, how every organ of our body is working, and even control our heartbeats.

The thyroid plays a crucial role in our body. The thyroid gland releases thyroid hormones and regulates the metabolism of the body. So, like any other hormones, thyroid hormones play a significant role in a woman’s life through menstruation to fertility to pregnancy and even until the baby’s development. Even a slight change in the level of thyroid hormones affects the pregnancy. Even if the level of thyroid hormones is more or less, both symptoms will be crucial during pregnancy. When our thyroid doesn’t work correctly, it can create a significant impact on our whole body.


If our body makes too many thyroid hormones, then the condition is called “hyperthyroidism,” in case it produces too few thyroid hormones, it is called “hypothyroidism.” The thyroid makes the hormones of T3 and T4 which controls and maintains the metabolism. It checks how the body is utilizing the energy and how it stores it. So let us know how it affects pregnancy.

 A hormone named estrogen plays an essential part during pregnancy, but a balanced thyroid hormone is equally necessary for conception and healthy pregnancy. While a woman is pregnant, both hyperthyroidism and hypothyroidism can negatively impact both mother and baby. So, I wanted to cover this article specifically on hyperthyroidism and pregnancy.

Role of Thyroid Hormones

When the thyroid gland makes too many thyroid hormones T3 & T4, it is stated as an overactive thyroid or hyperthyroidism. Due to which an increased number of thyroid hormones also causes a low level of thyroid-stimulating hormone (TSH). The pituitary gland produces this TSH; this tells the thyroid gland about how much thyroid hormone needs to be secreted to the blood. But if the T3 and T4 are released more than it needs to the body, it may affect the TSH level, and it will shut down the production of TSH.

Overactive thyroid or hyperthyroidism increases the metabolism, which means it will increase energy usage; when there’s an overactive thyroid, it may lead to rapid functioning heart rate, elevated blood pressure, and many more severe health hazard issues. The issues caused by the thyroid can be hard to diagnose during pregnancy.

Why? There are some symptoms of thyroid that can mimic the hormonal changes of a woman who’s having a normal pregnancy. Pregnant women with uncontrolled and untreated hyperthyroidism can develop high blood pressure. It also causes problems during pregnancy like the risk of miscarriage, premature birth, or having a baby of low birth weight.


Hyperthyroidism Before Pregnancy

Hyperthyroidism will affect pregnancy, but it also affects a woman’s body even before pregnancy; hyperthyroidism can also affect a woman’s fertility. It can create complications for getting pregnant and the ability to carry a baby till the final period. One of the main reasons or causes of overactive thyroid or hyperthyroidism for a woman is the grave’s disease. Grave’s disease is an immune system disorder that produces more thyroid hormones than needed; this situation is called hyperthyroidism.

Although there are many reasons which cause hyperthyroidism, but this one is one of the major causes behind the cause of hyperthyroidism. A woman having hyperthyroidism doesn’t mean that she’ll never get pregnant or won’t have healthy pregnancy; it’s not the issue. If she gets proper treatment, then there are very few chances to have such problems. Still, if it’s untreated, the situation arises; it can cause many severe complications during pregnancy and even before pregnancy. In case this is untreated, it tends to irregular in periods, leading to difficulties in conceiving.

Importance of Thyroid function checkup

Before planning for a baby, a woman should go through necessary blood tests to check the thyroid functions. Over secretion of thyroid hormone can impact infertility by causing difficulty in fertilization of egg and also cause trouble during implantation. A high level of thyroid hormones can affect the health of the mother as well as the baby.

So, it is vital to regularly get a check-up on the levels of thyroid secretion during pregnancy because if there are any changes in the level of thyroid hormone secretion, then there is a need to take medication that help to control. Even while taking drugs, one should also consult a doctor and have a proper check-up. When a pregnant woman takes thyroid medications, it crosses through the placenta, so the lowest possible dose is required to affect the baby.


During pregnancy, if a mother has hyperthyroidism and is taking antithyroid drugs, it may affect the development of a baby and cause abnormalities. If the dosage of anti-thyroid is too high, then the baby’s thyroid may also be affected and may also become under-active, and it tends the baby to develop goiter.

But during pregnancy, a mother shouldn’t stop taking medications because untreated hyperthyroidism is much dangerous than an anti-thyroid medication. Other than antithyroid drugs, hyperthyroidism can also be treated by few other methods like one can have surgery where a part of the thyroid is removed, and the other way is they can take radioactive iodine treatment.

A woman who plans to get pregnant shouldn’t go through radioactive iodine treatment. This treatment usually destroys the patient’s thyroid gland and may stop it from being overactive, which can also harm the baby’s thyroid gland. This radiation affects the eggs within the ovaries; that’s why when a woman is going under radioactive treatment, she should avoid pregnancy for 6-12 months.

Other Options

A woman with hyperthyroidism can have surgery to remove a part of the thyroid gland while she’s pregnant but during the second trimester only, i.e., between 4months to 6months. The most important fact is that a woman shouldn’t go through radioactive treatment even after delivering a baby because she will be breastfeeding the baby, which may severely affect the baby’s health. In contrast, she can have anti thyroid drugs after consulting her physician. Some signs or symptoms of hyperthyroidism, which generally occur during pregnancies, include faster heart rate, causes trouble of heat and tiredness, shaky hands, and weight loss.

So, a woman can help and ensure both her and baby’s health by regularly consulting with her gynecologist and endocrinologist. An endocrinologist is a specialist who treats related hormonal conditions. Hence, a woman can have a healthy pregnancy if she’s having an overactive or can be said as hyperthyroidism if she is in contact with her physician regularly and follow their instructions accordingly.

Antara Chowdhary

Antara Chowdhury is a Content Marketer and Strategist with 6 years of experience. She is Master degree holder in Journalism and wants to explore everything she can write on.

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