Hashimoto’s thyroiditis

Hashimoto’s thyroiditis is an autoimmune disorder in which the body’s immune system mistakenly attacks healthy cells in the thyroid gland. Other names for this condition are Hashimoto’s disease, chronic lymphocytic thyroiditis, and chronic autoimmune thyroiditis. 

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The thyroid is a small organ in the front of your neck that produces essential hormones which influence many bodily functions, including metabolism and fertility. Hashimoto’s thyroiditis is the leading cause of hypothyroidism, a condition where the thyroid doesn’t make enough hormones. 
Not everyone with Hashimoto’s has hypothyroidism, but the condition usually results in a decline of thyroid hormones because it destroys the thyroid gland, leading to hypothyroidism at some point.

Impact of Hashimoto’s thyroiditis on fertility

Hashimoto’s thyroiditis can make getting pregnant more challenging and raise the risk of pregnancy complications. This is because it can lead to decreased thyroid hormone production, which significantly influences your reproductive hormones.

Hypothyroidism can suppress ovulation – and without ovulation, there’s no egg ready to be fertilized by sperm, making conception impossible. It can also interfere with implantation of a fertilized egg into the uterus, which is a possible reason for in vitro fertilization to be unsuccessful. During pregnancy, not having enough thyroid hormones can cause miscarriage, high blood pressure, gestational diabetes, placental abruption, premature birth, stillbirth, and low birth weight.

Potential causes of Hashimoto’s thyroiditis

Experts are unsure what causes someone’s immune system to destroy healthy thyroid cells. It could be triggered by one or more of the following factors:

• Genetic conditions
• Infection
• Stress
• Exposure to radiation
• Another autoimmune condition (Addison’s disease, type 1 diabetes, etc.) 
• Previous pregnancy
• High iodine diet

Hashimoto’s disease is much more common in women and middle-aged people.

Symptoms of Hashimoto’s thyroiditis

Hashimoto’s thyroiditis causes inflammation of the thyroid gland. A common first symptom of Hashimoto’s is a goiter, or enlarged thyroid. This can cause a feeling of fullness and swelling in the neck and throat. 

Other physical signs of Hashimoto’s disease and hypothyroidism are:

• Heavy or irregular periods
• Fatigue
• Weight gain
• Cold sensitivity
• Joint stiffness and muscle pain
• Constipation
• Depressive mood
• Puffiness in the eyes and face
• Thin hair or hair loss
• Slow heartbeat
• Trouble with memory or concentration
• Brittle nails
• Enlarged tongue

Diagnosis of Hashimoto’s thyroiditis

Doctors diagnose Hashimoto’s thyroiditis by asking about your medical history and symptoms, performing a physical exam to check for a goiter and signs of hypothyroidism, and doing a few blood tests. 

Lab tests include measuring your levels of thyroid-stimulating hormone (TSH), thyroxine 4 (T4), and antithyroid antibodies. You may also have an ultrasound of your thyroid gland.

Treatment to improve fertility

Treatment for Hashimotos’ thyroiditis isn’t always necessary, if it’s not causing your thyroid to underproduce hormones. Your doctor may recommend simple observation to see how it develops. 

If autoimmune thyroid disease is causing hypothyroidism, you will be prescribed treatment with a medication called levothyroxine (or L-thyroxine). This replaces the missing thyroid hormones and makes your thyroid function normally again. 

Once your thyroid hormones are at a healthy level, you should be able to conceive and have a healthy pregnancy. A study found that over 76% of infertile women with hypothyroidism got pregnant within 6 weeks to 1 year after starting treatment with levothyroxine.

To boost the health of your thyroid and immune system and improve fertility, be sure to lead a healthy lifestyle by eating a balanced diet and getting regular exercise. Vitamin D, iron, and zinc supplements can boost thyroid health and fertility too, so talk to your doctor about starting supplementation. 

As soon as you get pregnant, inform your OB-GYN about your autoimmune thyroid condition. You’ll need to be more closely monitored during pregnancy and may need to alter your treatment plan.

This article has been verified by a medical professional

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