Thyroid Testing During Pregnancy: Why It Matters

You being pregnant can change so much for you, including your thyroid. Your thyroid gland plays a huge part for you to regulate your hormones and metabolism. Both of those can play a part in a healthy pregnancy and development of your new bundle of joy.  

What Is Thyroid Testing? 

Thyroid testing is what doctors use to check on the overall health of your thyroid gland. Your thyroid gland is a butter-fly shaped organ that is located in your neck. That butter-fly shaped thing is responsible for getting your hormones and metabolism in order.

The thyroid profile lab test includes thyroid blood testing to assess the levels of thyroid-stimulating hormone (TSH), T4 (thyroxine), T3 (triiodothyronine), and thyroid antibodies. Sometimes, image tests are requested to have a better look at the thyroid gland to make sure things are normal. These include thyroid scans and ultrasounds.  

Also Read: Understanding Thyroid Hormones: What Is the Difference Between T3 and T4?

Importance of Thyroid Testing Among Pregnant Women

For pregnant women, thyroid testing is often included in their prenatal checkups to ensure hormone levels are within the normal range. In addition, thyroid disorders become common during pregnancy. The most prevalent of which is hypothyroidism (underactive thyroid gland), affecting 3-5% of pregnant mothers(1). 

Getting your hormone levels checked regularly helps your health in the future by a long shot. Thyroid blood tests, for instance, allow your doctor to check for abnormalities and prescribe the appropriate medical intervention to protect your health and your baby’s. 

Moreover, those with existing thyroid conditions should  continue to monitor their thyroid hormones especially when they are pregnant. It’s important to find any existing thyroid issues so your doctor can closely monitor you and your health.

Impact of Thyroid Problems During Pregnancy

While you are prego the impacts of thyroid disorders become more important as it extends the fetal growth and your overall development during the trimester. Thus, thyroid testing is necessary to prevent any lasting damage and the known consequences of thyroid disorders, such as premature birth and fetal complications. 

Getting your thyroid hormones checked, especially TSH, is also often included in routine or annual checkups due to its relevance in maintaining general health and wellness. Thyroid problems may influence cardiovascular risks(2), mental health(3), and even hair loss(4). These may cause problems during pregnancy. 

There are two types of common thyroid problems: hypothyroidism and hyperthyroidism. Hypothyroidism means you’re not producing as much hormones. Both disorders may hinder a healthy pregnancy and fetal development(5). 

Its effects on maternal health

Pregnant women may have varied experiences as to the general symptoms influenced by hormonal changes. The same can be said when it comes to thyroid problems. However, the impact of untreated or unmanaged health issues with this organ can be a common ground. These often include the following:

Hypothyroidism:

• Weight gain
• Fatigue 
• Constipation
• Depression
• Problem focusing
• Risk of preeclampsia, miscarriage, and postpartum hemorrhage

Hyperthyroidism:

• Heat intolerance
• Sudden weight loss
• Tremors 
• Anxiety 
• Risk of preeclampsia and pregnancy-induced hypertension

A critical factor in the magnification of these consequences is the lack of detection and proper management. Fortunately, regular monitoring and appropriate treatment can help mitigate these risks and conditions. 

Its effects on fetal health

The thyroid gland produces hormones that are essential for the baby’s brain development(6) and overall health. Thus, abnormalities in its function can significantly dictate the outcome of fetal growth. Specifically, failure to address thyroid problems may lead to the following:

Hypothyroidism:

• Brain cognitive development
• Lower IQ (intelligence quotient)
• Low birth weight
• Risk of stillbirth 

Hyperthyroidism: 

• Preterm birth
• Low birth weight 
• Fetal hyperthyroidism(7) (rare case for those with Basedow-Grave’s disease)

The fact that thyroid disorders can have a direct influence on fetal development makes it more significant for women to undergo thyroid testing during pregnancy. This is especially true since many symptoms of thyroid dysfunction can mimic common pregnancy symptoms, making them easily overlooked.

When To Undergo Thyroid Testing During Pregnancy

Most doctors that you go to will always include a thyroid blood test as part of the prenatal journey, especially if you have risk factors like family history, autoimmune disease, or symptoms of thyroid problems. 

You should be visiting during your first trimester and that is when fetal brain development begins. Thus, if you miss any critical thyroid disorder, it may impact the baby’s cognition. 

If you have a known thyroid disorder (hypothyroidism or hyperthyroidism), your doctor will likely monitor your thyroid levels every 4-6 weeks, especially in the first half of the pregnancy, to adjust medication as needed.

Frequently Asked Questions

How do you control thyroid levels during pregnancy?

Checking your thyroid levels during these pregnancy checkups is the first step to controlling it. If your obstetrician diagnoses thyroid overactivity or underactivity, you’ll likely be prescribed medication to address the condition. 

For instance, levothyroxine is often recommended for women with hypothyroidism. Your doctor may align the dosage throughout your pregnancy as your hormone levels fluctuate.        

Which fruit is good for the thyroid during pregnancy?

Berries, especially strawberries and blueberries, are the top recommended fruits for thyroid health during pregnancy. This is due to their rich levels of antioxidants that protect the thyroid from damage from oxidative stress. Other fruits to include in your diet are bananas, apples, and citrus, which strengthen your immune system.    

What foods should I avoid with thyroid issues?

The type of food you should avoid if you have thyroid issues depends on the condition that impairs the organ’s function. 

For example, if the problem has something to do with iodine uptake, stir clear from foods that inhibit its absorption, like soy, raw broccoli, and highly processed foods (e.g., cured meat, sugary drinks, potato chips). Ask your doctor regarding the specific foods to avoid for a more personalized approach to your diet.  

In a Nutshell

Taking a thyroid test is one of the steps you can ensure that you have a healthy pregnancy and that your baby’s development remains unhindered. Pay attention to any symptoms related to thyroid disorders and don’t hesitate to talk to your obstetrician about concerns related to these conditions. Additionally, make sure your diet has the necessary nutrients required to keep a healthy thyroid function. can ensure that you have a healthy pregnancy and that your baby’s development remains unhindered. Pay attention to any symptoms related to thyroid disorders and don’t hesitate to talk to your obstetrician about concerns related to these conditions. Additionally, make sure your diet has the necessary nutrients required to keep a healthy thyroid function.

Sources 

¹ Abadi KK, Jama AH, Legesse AY, Gebremichael AK. Prevalence of Hypothyroidism in Pregnancy and Its Associations with Adverse Pregnancy Outcomes Among Pregnant Women in A General Hospital: A Cross Sectional Study. Int J Womens Health. 2023 Oct 3;15:1481-1490. doi: 10.2147/IJWH.S429611. PMID: 37810201; PMCID: PMC10559790.

² Paschou SA, Bletsa E, Stampouloglou PK, Tsigkou V, Valatsou A, Stefanaki K, Kazakou P, Spartalis M, Spartalis E, Oikonomou E, Siasos G. Thyroid disorders and cardiovascular manifestations: an update. Endocrine. 2022 Mar;75(3):672-683. doi: 10.1007/s12020-022-02982-4. Epub 2022 Jan 15. PMID: 35032315.

³ Lekurwale V, Acharya S, Shukla S, Kumar S. Neuropsychiatric Manifestations of Thyroid Diseases. Cureus. 2023 Jan 20;15(1):e33987. doi: 10.7759/cureus.33987. PMID: 36811059; PMCID: PMC9938951.

⁴ Hussein RS, Atia T, Bin Dayel S. Impact of Thyroid Dysfunction on Hair Disorders. Cureus. 2023 Aug 10;15(8):e43266. doi: 10.7759/cureus.43266. PMID: 37692605; PMCID: PMC10492440.

⁵ Joshi JS, Shanoo A, Patel N, Gupta A. From Conception to Delivery: A Comprehensive Review of Thyroid Disorders and Their Far-Reaching Impact on Feto-Maternal Health. Cureus. 2024 Feb 1;16(2):e53362. doi: 10.7759/cureus.53362. PMID: 38435202; PMCID: PMC10907906.

⁶ Bernal J. Thyroid Hormones in Brain Development and Function. [Updated 2022 Jan 14]. In: Feingold KR, Anawalt B, Blackman MR, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK285549/
⁷ Soto J, Weissglas B, von Plessing-Pierry G, Del Solar MP, Peña-Villa C, Flores X, Arancibia M, Campos L. Fetal Hyperthyroidism Secondary to Maternal Basedow-Graves’ Disease. AJP Rep. 2024 May 31;14(2):e176-e183. doi: 10.1055/a-2317-9431. PMID: 38827649; PMCID: PMC11142847.