Hashimotos + MTHFR + Fertility: What’s the connection?

What is Hashimoto’s Thyroiditis?

Hashimoto’s thyroiditis, also known as Hashimoto’s disease, is an autoimmune disorder that affects the thyroid gland. In this condition, the body’s immune system attacks the thyroid gland, which can cause inflammation and damage to the gland over time. This can lead to an underactive thyroid (hypothyroidism) as the thyroid gland becomes less able to produce thyroid hormones, which regulate metabolism in the body. Hashimoto’s is one of the most common causes of hypothyroidism and is more commonly seen in women than men. 

Symptoms of Hashimoto’s can include:

• fatigue
• weight gain
• sensitivity to cold
• joint and muscle pain
• depression
• thinning hair. 

Treatment usually involves medication to replace the missing thyroid hormone, as well as management of any associated symptoms.

How does Hashimoto’s Impact Fertility?

Hashimoto’s thyroiditis can potentially affect fertility in several ways, although the exact mechanisms are not completely understood.

First, thyroid hormones play a crucial role in regulating the menstrual cycle and ovulation in women. Women with hypothyroidism due to Hashimoto’s thyroiditis may experience irregular menstrual cycles, anovulation (lack of ovulation), or even amenorrhea (absence of menstruation). This can make it more difficult to conceive.

Second, Hashimoto’s thyroiditis is an autoimmune disorder, and some studies suggest that autoimmune disorders can increase the risk of infertility. The exact reason for this is not clear, but it may be related to inflammation in the reproductive system or other effects on hormone levels.

Furthermore, women with untreated or poorly managed Hashimoto’s thyroiditis may have higher rates of miscarriage and pregnancy complications such as preterm birth, preeclampsia, and foetal growth restriction.

However, it is important to note that not all women with Hashimoto’s thyroiditis will experience fertility problems, and with appropriate treatment and management, many women are able to conceive and have healthy pregnancies.

If you are concerned about how Hashimoto’s may be affecting your fertility, please speak to one of our practitioners for personalised advice and guidance.

What Causes Hashimotos?

Hashimoto’s thyroiditis is an autoimmune disorder, which means that it occurs when the body’s immune system mistakenly attacks its own tissues. In the case of Hashimoto’s, the immune system targets the thyroid gland, causing inflammation and damage over time.

The exact cause of Hashimoto’s thyroiditis is not fully understood, but it is thought to be the result of a combination of genetic and environmental factors. Certain genetic variations may make some people more susceptible to developing autoimmune disorders like Hashimoto’s. Environmental triggers, such as viral infections or exposure to toxins, may also play a role in triggering the autoimmune response in susceptible individuals.

Other risk factors for developing Hashimoto’s thyroiditis include being female, having a family history of thyroid or autoimmune disorders, and having certain other autoimmune disorders such as type 1 diabetes or celiac disease.

It is important to note that not everyone who has these risk factors will develop Hashimoto’s thyroiditis, and the condition can also occur in people without any known risk factors.

What is the link between Hashimotos and MTHFR polymorphisms?  

​​MTHFR (methylenetetrahydrofolate reductase) is an enzyme that plays a critical role in the metabolism of folate and homocysteine. Variations in the MTHFR gene have been associated with reduced enzyme activity, which can affect folate and homocysteine levels in the body. These variations have been linked to a number of health conditions, including thyroid disease.

Studies have suggested that MTHFR gene variations may be associated with an increased risk of developing autoimmune thyroid disease, including Hashimoto’s thyroiditis and Graves’ disease. One specific MTHFR gene variant, known as the C677T polymorphism, has been the most extensively studied in relation to thyroid disease.

The C677T polymorphism involves a change in the DNA sequence of the MTHFR gene that leads to reduced enzyme activity. This can result in elevated homocysteine levels, which have been linked to inflammation and oxidative stress, both of which are known to play a role in autoimmune disease.

Homocysteine is a byproduct of methionine metabolism that is normally converted into methionine or cysteine with the help of the MTHFR enzyme. However, individuals with the C677T polymorphism have reduced MTHFR activity, leading to higher homocysteine levels. Elevated homocysteine levels have been linked to oxidative stress, which can damage cells and tissues in the body, and inflammation, which can contribute to autoimmune diseases like Hashimoto’s thyroiditis.

In addition, folate deficiency, which can result from impaired MTHFR activity, has been linked to an increased risk of autoimmune thyroid disease. Folate is essential for DNA synthesis and repair, as well as for the regulation of immune function, and deficiencies can impair immune function and increase susceptibility to autoimmune disease.

Other factors to Consider:

1. Gut

There is a growing body of research suggesting that there may be a link between gut health and Hashimoto’s thyroiditis. The theory behind this link is that an unhealthy gut microbiome (the collection of bacteria and other microorganisms in the gut) can contribute to the development or exacerbation of autoimmune diseases, including Hashimoto’s thyroiditis.

Here are some ways in which gut health may be linked to Hashimoto’s thyroiditis:

1. 1. Leaky gut: In some individuals, a leaky gut (increased intestinal permeability) may allow harmful substances, such as toxins and undigested food particles, to pass into the bloodstream. This can trigger an immune response that may contribute to the development of autoimmune diseases, including Hashimoto’s thyroiditis.
   2. Dysbiosis: Dysbiosis refers to an imbalance in the gut microbiome that may result in an overgrowth of harmful bacteria and a reduction in beneficial bacteria. This imbalance may contribute to inflammation and immune dysfunction, which may in turn contribute to the development or exacerbation of autoimmune diseases.
   3. Nutrient absorption: The gut plays a critical role in nutrient absorption, and a compromised gut may lead to nutrient deficiencies that can negatively impact thyroid function and contribute to the development or exacerbation of Hashimoto’s thyroiditis.
   4. Immune system regulation: The gut microbiome plays an important role in regulating immune system function. An unhealthy gut may contribute to immune system dysfunction, which may in turn contribute to the development or exacerbation of autoimmune diseases.

2. Additional genetics

Additional genetic polymorphisms have been identified that may contribute to the development of Hashimoto’s thyroiditis. Some of these include:

1. 1. Human leukocyte antigen (HLA) genes: Certain variants of the HLA genes have been linked to an increased risk of developing autoimmune disorders like Hashimoto’s thyroiditis. These genes play a role in regulating the immune system, and variations in these genes may affect how the immune system recognizes and responds to the body’s own tissues.
   2. Cytokine genes: Cytokines are proteins that help to regulate the immune system. Variations in genes that code for cytokines, such as interleukin-10 (IL-10) and tumour necrosis factor-alpha (TNF-alpha), have been associated with an increased risk of developing Hashimoto’s thyroiditis.
   3. CTLA-4 gene: The CTLA-4 gene codes for a protein that helps to regulate the activity of immune cells. Certain variants of this gene have been linked to an increased risk of developing Hashimoto’s thyroiditis, as well as other autoimmune disorders.
   4. PTPN22 gene: The PTPN22 gene codes for a protein that helps to regulate the activity of immune cells. Variations in this gene have been associated with an increased risk of developing autoimmune disorders, including Hashimoto’s thyroiditis.
   5. TSHR gene: The TSHR gene codes for the receptor that binds thyroid-stimulating hormone (TSH) and regulates the production of thyroid hormones. Variations in this gene have been linked to an increased risk of developing Hashimoto’s thyroiditis.

3. Environmental

There is ongoing research on the potential environmental factors that may contribute to the development of Hashimoto’s thyroiditis. Some factors that have been suggested as potential triggers or contributors to the disease include:

1. 1. Exposure to radiation: Exposure to high levels of radiation, such as during nuclear accidents or medical treatments, may increase the risk of developing Hashimoto’s thyroiditis.
   2. Chemical exposure: Exposure to certain chemicals, such as pesticides, solvents, and industrial chemicals, may increase the risk of developing Hashimoto’s thyroiditis.
   3. Infections: Some infections, such as viral infections or chronic bacterial infections, may trigger or contribute to the development of Hashimoto’s thyroiditis.
   4. Iodine intake: High levels of iodine intake or insufficient intake,  may increase the risk of developing Hashimoto’s thyroiditis in individuals who are genetically susceptible to the disease.
   5. Stress: Chronic stress may contribute to the development or exacerbation of Hashimoto’s thyroiditis by affecting immune system function.

How To Improve Your Fertility if you have Hashimoto’s and MTHFR

Here are 10 steps that someone with Hashimoto’s thyroiditis can take to improve their fertility:

1. Work with a qualified professional: It’s important to work with a healthcare provider who can monitor thyroid function and provide guidance on managing Hashimoto’s thyroiditis and optimising fertility.
2. Optimise thyroid hormone levels: Maintaining optimal thyroid hormone levels is essential for fertility. This may involve taking thyroid hormone replacement medication and monitoring thyroid function regularly.
3. Optimise Homocysteine and MTHFR: Understand the right amount of folate, B12 and other nutrients needed for your polymorphism and aim to optimise methylation and homocysteine metabolism before conceiving.
4. Address nutrient deficiencies: Nutrient deficiencies, such as low levels of iron, vitamin D, and selenium, zinc, can negatively impact thyroid health and fertility. 
5. Reduce stress: Chronic stress can affect fertility by disrupting hormone levels and ovulation. Techniques such as mindfulness meditation, yoga, and acupuncture may help reduce stress.
6. Maintain a healthy weight: Both underweight and overweight can negatively impact fertility. 
7. Eat a healthy diet: A balanced diet that includes plenty of fruits, vegetables, lean protein, and healthy fats can support fertility. Explore whether grains are contributing to thyroid disease progression. Learn about the impact of cruciferous vegetables that can reduce thyroid function further. 
8. Avoid environmental toxins: Exposure to environmental toxins, such as pesticides and heavy metals, can negatively impact fertility. Minimising exposure to these toxins can be helpful.
9. Monitor ovulation: Monitoring ovulation can help identify the optimal time for conception. Methods for monitoring ovulation include tracking menstrual cycles, monitoring basal body temperature, and using ovulation predictor kits.
10. Heal your gut: Work with a practitioner to improve your gut health and immune function within the gut. 

References

1. American Thyroid Association. (2020). Hashimoto’s Thyroiditis. Retrieved from https://www.thyroid.org/hashimotos-thyroiditis/
2. Busnelli, A., Paffoni, A., Fedele, L., & Somigliana, E. (2019). The impact of thyroid autoimmunity on IVF/ICSI outcome: a systematic review and meta-analysis. Human Reproduction Update, 25(4), 459-478.
3. Garber, J. R., Cobin, R. H., Gharib, H., Hennessey, J. V., Klein, I. L., Mechanick, J. I., … & Woeber, K. A. (2012). Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocrine Practice, 18(6), 988-1028.
4. Krysiak, R., & Okopień, B. (2016). The effect of levothyroxine and selenomethionine on lymphocyte and monocyte cytokine release in women with Hashimoto’s thyroiditis. The Journal of Clinical Endocrinology & Metabolism, 101(5), 1975-1982.
5. Krysiak, R., & Okopień, B. (2018). The effect of vitamin D on thyroid autoimmunity in euthyroid women with Hashimoto’s thyroiditis and positive anti-TPO antibodies. Pharmacological Reports, 70(2), 292-297.
6. Lambadiari, V., Mitrou, P., Maratou, E., & Raptis, S. A. (2019). Gut microbiota and diabetes mellitus. Diabetes Research and Clinical Practice, 157, 107852.
7. National Institute of Diabetes and Digestive and Kidney Diseases. (2021). Hashimoto’s Disease. Retrieved from https://www.niddk.nih.gov/health-information/endocrine-diseases/hashimotos-disease
8. Nishimura, Y., & Kimura, K. (2019). Gut microbiota and autoimmune thyroid diseases. Endocrine Journal, 66(3), 213-220.
9. Román, G. C., Ghassabian, A., Brinton, R. D., Lyketsos, C., & Lerner, A. J. (2019). The Women’s Alzheimer’s Movement Prevention Center: A vision for protecting female brain health. Journal of Prevention of Alzheimer’s Disease, 6(3), 179.
10. Wentz, I. (2017). Hashimoto’s Protocol: A 90-Day Plan for Reversing Thyroid Symptoms and Getting Your Life Back. HarperOne.