Thyroid is one of the endocrine glands that regulate our body’s metabolism by releasing Thyroid hormones. This glad is prone to some changes during pregnancy to efficiently address the increased need for metabolism.
This post aims to explore these changes and discuss ways to support pregnancy through a normally functioning Thyroid. It is important to mention that this blog does not aim to replace the individualized care provided by healthcare professionals and only serves to inform our audience. It is recommended to rely on your healthcare provider for the most reliable treatment options and personalized goals.
Thyroid Function
The Thyroid function is regulated through different signaling pathways involving parts of our brain, the Thyroid gland, and the target organs in our body. These hormones include Thyroid-Releasing Hormone (TRH), Thyroid-Stimulating Hormone (TSH), and Thyroid hormones, including Thyroxine (T4) and Triiodothyronine (T3). Thyroid induces its effects by adjusting the production and release of T3 and T4.
Exploring the in-depth function of each component is beyond the scope of this article. However, their overall function includes the regulation of metabolism, growth, and development, as well as organogenesis in pregnancy. The Thyroid function is mostly assessed by studying TSH, T3, and T4 levels in our bloodstream.
In general, decreased Thyroid function, known as Hypothyroidism, as well as increased Thyroid function (Hyperthyroidism) are two ways that the Thyroid function may be disturbed. We will discuss each scenario in further detail below.
Thyroid and Pregnancy
Studies reveal that Thyroid hormone requirements increase by about 30 to 40% during pregnancy to support the growth and development of the fetus and increased metabolism by the mother. This increase is observed early in pregnancy, sometimes even before the parents are aware of their pregnancy. While this does not generally require Thyroid hormone treatments in previously healthy mothers with adequate dietary intake, in some cases, especially in those with overt hypothyroidism, this may require dose adjustments in previous medications.
Additionally, Iodine requirements also increase during pregnancy to support the increased function of the Thyroid gland. As a result, mild-to-moderate Iodine deficiency is not uncommon among expecting women.
Most people obtain Iodine through dietary intake from iodized salt, seafood, and dairy products. While this is typically enough to address the increased Iodine need throughout pregnancy, special attention should be given to those with a restricted diet (such as a vegetarian diet or those using non-iodized salts) due to the risk of iodine deficiency in pregnancy.
Hypothyroidism
Hypothyroidism typically leads to lower-than-normal Thyroid hormones (T3, T4) in the bloodstream. Patients may experience signs and symptoms such as cold intolerance, dry skin, hair loss, sleep disturbances, weight gain, appetite changes, and constipation. This will also affect organ development and the natural progress of pregnancy.
While this may be caused by a variety of medical conditions, such as autoimmune states and post-thyroid resection surgery, it is not uncommon for women to be in a hypothyroid state at the beginning of their pregnancy.
Considering the increased need for Thyroid function and hormones throughout pregnancy, Thyroid function needs to be properly assessed, ideally before conception, to enter pregnancy with normal Thyroid hormone levels and provide for the best possible outcome and minimize the risk of complications. This highlights the importance of proper assessment and pre-conception counseling to help identify any need for medication adjustments before pregnancy.
Hyperthyroidism
As previously mentioned, the need for Thyroid hormones increases throughout pregnancy. As a result, pregnancy-induced Hyperthyroidism is not as common as Hypothyroidism, especially among otherwise healthy individuals.
Hyperthyroidism leads to increased Thyroid hormones in our bloodstream, leading to symptoms such as heat intolerance, excessive sweating, moist skin, heart racing, and high blood pressure. This will also interfere with the normal progress of pregnancy and needs to be corrected for an optimal outcome.
If you are suffering from Hyperthyroidism, it is important to consult your physician for possible medication adjustments throughout pregnancy, as some Hyperthyroidism medications are not allowed during gestation or breastfeeding.
Thyroid Medication
The physiological increase in Thyroid hormone requirements does not typically lead to a need for medications in healthy individuals. However, in select cases, this need may develop, and dose adjustments may be required for those previously under treatment with Thyroid hormones (such as levothyroxine). It is recommended to seek professional and individualized advice regarding your treatment options to maintain normal Thyroid function throughout pregnancy from your healthcare provider.
Something to consider is the timing of medications, as they may interfere with other supplements, such as Iron or Calcium. It is generally advised to separate levothyroxine from any iron or calcium supplements by at least 4 hours to prevent absorption interference.
The response to medications is assessed through serial TSH, T3, and T4 levels studies, and doses are adjusted to achieve normal levels and the absence of any signs of symptoms.
Conclusion
To summarize, Thyroid hormone requirements typically increase early in pregnancy. This may not lead to a need for medications in many patients, as dietary iodine intake usually suffices to address this need. However, it is important to assess thyroid function and address any need for medication adjustments before the start of pregnancy, especially in those suffering from underlying conditions, such as overt Hypothyroidism.
For the most reliable advice on how to manage normal Thyroid function throughout pregnancy, it is recommended to contact your healthcare provider and seek individualized care.
