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Doctor examining a man's throat for hypothyroidism

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Hypothyroidism and male fertility

Hypothyroidism is a condition that develops when your thyroid gland doesn’t make enough thyroid hormone. Hypothyroidism affects many of your body’s systems, and while the condition is less common in men than women, hypothyroidism and male fertility are also linked. We look into male symptoms of hypothyroidism, its effects on male fertility, and how you can treat hypothyroidism for improved health and fertility.

Key takeaways

  • Hypothyroidism occurs when your body makes insufficient thyroid hormone.
  • Symptoms of hypothyroidism include fatigue, a slow heart rate, dry skin, and depression.
  • In people with testes, hypothyroidism may be associated with low testosterone levels, reduced semen volume, and delayed ejaculation.
  • The purpose of hypothyroidism treatment is to replenish your thyroid hormone levels, which may improve your fertility.

What is hypothyroidism?

Hypothyroidism, which is also known as underactive thyroid, is a condition that occurs when the thyroid gland in your neck makes too little thyroid hormone. Thyroid hormone plays a vital role in your body’s energy usage. As a result, if there’s insufficient thyroid hormone, many of your body’s processes slow down.

Hypothyroidism affects almost 5% of Americans aged 12 and above. In many cases, people with the condition have few noticeable symptoms.

Hypothyroidism vs. hyperthyroidism

Hypothyroidism is the opposite of hyperthyroidism, which happens when your thyroid gland makes too much thyroid hormone. This condition, also called overactive thyroid, speeds up your body’s processes and can cause symptoms including weight loss, quick heartbeat, and muscle weakness. Symptoms are often different in different people.

Hyperthyroidism is less common than hypothyroidism. Overactive thyroid affects only around 1% of Americans aged 12 and above, mainly women and people over age 60.

Symptoms of hypothyroidism

Hypothyroidism symptoms may include:

  • often feeling cold
  • slow heart rate
  • feeling tired
  • constipation
  • joint pain
  • dry skin
  • depression
  • brittle hair or nails
  • weight gain
  • fertility issues
  • heavy menstrual periods

Hypothyroidism symptoms in males may also appear as:

  • hair loss
  • muscle weakness
  • low sex drive
  • erectile dysfunction
  • delayed ejaculation

Hypothyroidism takes time to develop, so you may have the condition for months or years before you notice its symptoms. At the same time, many of the symptoms are common and may be related to conditions other than hypothyroidism.

If you don’t receive treatment, hypothyroidism can lead to:

  • high cholesterol
  • reduced taste and smell
  • slower rate of talking
  • hoarseness
  • puffy face
  • decreased body temperature
  • in rare cases, myxedema coma (a medical emergency where your body’s processes slow to a critical level)

What causes hypothyroidism?

There are several possible causes of hypothyroidism, including:

  • Thyroiditis: This condition, defined as inflammation of the thyroid gland, may happen as a result of your immune system targeting the thyroid gland, pregnancy (called postpartum thyroiditis), or a viral infection. The swelling causes the thyroid gland to release too much thyroid hormone, increasing its level in your blood and causing thyrotoxicosis. This can then lead to your thyroid producing too little thyroid hormone.
  • Hashimoto’s disease: This autoimmune disorder is a type of thyroiditis. With this condition, the immune system attacks and damages the thyroid. This is the most common reason for hypothyroidism.
  • Sheehan syndrome: This condition involves heavy bleeding during childbirth that damages the pituitary gland, leading to hypothyroidism. The pituitary gland is responsible for releasing thyroid stimulating hormone (TSH), which tells your thyroid to make thyroid hormone.
  • Congenital hypothyroidism: This type of hypothyroidism affects you from birth and may result from your thyroid gland not developing correctly.
  • Certain medications: Lithium (for mood disorders), amiodarone (for irregular heart rhythms), and chemotherapy (for cancer) can all lead to hypothyroidism.
  • Surgery: Removing sections of the thyroid gland, or the entire gland, can cause hypothyroidism.
  • Radiation therapy: Radiation that targets cancers in your neck or brain can harm your thyroid gland, leading to hypothyroidism.
  • Radioactive iodine: Taking radioactive iodine to intentionally damage the thyroid gland as a treatment for hyperthyroidism may lead to hypothyroidism.
  • Pituitary tumor: A tumor that affects the pituitary gland’s ability to release TSH can result in hypothyroidism.
  • Iodine deficiency: Consuming too little iodine can cause hypothyroidism, but this occurs very infrequently in the U.S.

You have a higher risk of developing hypothyroidism if you:

  • are female
  • are an older adult
  • are white
  • have an autoimmune disease like type 1 diabetes or celiac disease
  • have Down syndrome or Turner syndrome
hypothyroidism and male fertility: normal TSH levels 0.4–5.49 mIU/L

How is hypothyroidism diagnosed?

Your doctor will start by asking for your medical history and conducting a physical exam. If you have hypothyroidism, the physical exam may show an enlarged thyroid gland, increased diastolic blood pressure, and swelling in your arms or legs.

Since hypothyroidism symptoms can be the same as those present in other diseases and conditions, your doctor will likely conduct several tests to make sure it’s the correct diagnosis, such as:

  • Thyroid stimulating hormone (TSH) test: The pituitary gland in your brain produces TSH, which in turn directs the thyroid gland to make thyroid hormone. When your thyroid makes too little hormone, the pituitary gland will make more TSH. As a result, a blood test showing high TSH levels typically indicates hypothyroidism.
  • T4 test: Your thyroid makes two types of hormone, thyroxine (T4) and triiodothyronine (T3). If a blood test shows low T4 levels, you may have hypothyroidism. However, medications like corticosteroids can reduce T4 levels, so a low level doesn’t always mean you have hypothyroidism.
  • T3 test: A low T3 level can indicate hypothyroidism, but this additional test isn’t usually needed after the TSH and T4 tests to diagnose hypothyroidism.
  • Thyroid antibody tests: Autoimmune thyroid disorders like Hashimoto’s disease cause your immune system to make antibodies that attack the thyroid gland. An antibody test looks for these antibodies in your blood.
  • Ultrasound: An ultrasound uses sound waves to create images of your thyroid and check thyroid nodules, or growths on the thyroid gland, for cancer.

Your doctor may also run tests to check your cholesterol, sodium, and cortisol levels.

Treatment for hypothyroidism

The goal of hypothyroidism treatment is to bring your thyroid hormones up to a normal level. This is usually done with a medication called levothyroxine, which comes as a pill, liquid, or gel capsule and provides the same thyroid hormone that your thyroid would usually produce.

You’ll likely need to take the medication for the rest of your life to maintain your thyroid hormone levels. Your doctor will give you the smallest dose that provides the hormones you need and addresses your symptoms. They will regularly check your hormone levels, usually at least once per year, and adjust the medicine as needed.

You’ll need to keep taking your thyroid medicine even after your symptoms resolve. It’s also important to tell your doctor if you experience symptoms indicating that your medication dose might be too strong. These symptoms may include:

  • anxiety
  • losing weight quickly
  • sweating
  • shaking
  • heart palpitations

How hypothyroidism affects male fertility

While hypothyroidism is less common in people with sperm, recent research has shown a connection between hypothyroidism and male fertility. In males, hypothyroidism may lead to:

  • reduced levels of sex hormone binding globulin (SHBG), which affects your levels of active sex hormones
  • lower testosterone levels, which may affect sex drive and sperm production
  • decreased levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH), which impact reproduction
  • reduced semen volume
  • lower sperm motility
  • abnormal sperm morphology
  • low sex drive
  • erectile dysfunction
  • delayed ejaculation

Because of the negative impacts of hypothyroidism on male fertility, thyroid function tests may be helpful when assessing fertility issues in men. Hypothyroidism treatment may improve fertility in these cases.

What can hypothyroidism patients do to improve their fertility?

Treating your hypothyroidism may help improve your fertility if the thyroid issue was the cause of the problem.

There are other general steps you can take toward increased fertility, too. You may be able to improve your sperm and fertility through lifestyle changes, such as:

  • eating a healthy diet
  • getting regular exercise
  • reaching or maintaining a healthy weight
  • drinking alcohol only in moderation
  • stopping smoking
  • getting enough sleep
  • using fertility supplements

Getting a semen analysis can give you an idea of your fertility and areas you may be able to improve. You can easily and conveniently test your fertility with Legacy’s at-home semen analysis to get started on improving your sperm and preparing to build your family.

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