Hyperthyroidism and its effects on male and female fertility

Hyperthyroidism is a disorder of the thyroid gland that leads to excessive production of thyroid hormones. The most common cause of hyperthyroidism is Graves' disease, although it can also be caused by the presence of overactive thyroid nodules, inflammation of the gland or the administration of certain drugs.

The prevalence of hyperthyroidism is higher in women than in men. However, hyperthyroidism can cause problems in female and male fertility. In addition, this thyroid disorder can also lead to gestational complications if not treated correctly.

What is hyperthyroidism?

The thyroid gland is butterfly-shaped and located in the front area of the neck. It is responsible for secreting the thyroid hormones thyroxine (T4) and triiodothyronine (T3). These hormones are involved in the control of numerous vital functions of the body such as respiration, digestion, etc.

Hyperthyroidism, also known as overactive thyroidis a disorder of the thyroid gland caused by an excessive production of thyroid hormones. When there is a large amount of thyroid hormones in the body, the metabolism is accelerated, which leads to the manifestation of different symptoms.

This thyroid pathology is more frequent in the female population. In addition, some factors such as family history, high consumption of iodine-containing foods, administration of iodine-containing medications, etc. may cause an increased risk of hyperthyroidism.

Symptoms of excess thyroid hormones

Sometimes the symptoms of hyperthyroidism can be confused with other health problems. However, some typical clinical manifestations of hyperthyroidism are as follows:

• Cardiac arrhythmias.
• Weight loss.
• Tachycardia
• Nervousness and irritability.
• Increased desire to eat.
• Alterations of the menstrual cycle.
• Trouble sleeping.
• Hair loss.
• Increased sweating.
• High sensitivity to heat.
• Tremor in the hands.

Symptoms of hyperthyroidism

Another characteristic sign of people suffering from hyperthyroidism is exophthalmos, i.e., the protrusion of the eyes outward. In addition, osteoporosis, muscle weakness and decreased fertility or problems conceiving are other consequences of hyperthyroidism.

Why does hyperthyroidism occur?

The causes of hyperthyroidism are diverse. About 70% of hyperthyroidism cases are caused by Graves' disease. This disease usually manifests itself in women between the ages of 30 and 40. It is an autoimmune disorder, usually hereditary, in which antibodies are produced that stimulate the thyroid gland, causing increased hormone production.

Other possible causes of hyperthyroidism are:

• Hyperactive thyroid nodules, also known as Plummer's disease or toxic multinodular goiter.
• Thyroid inflammation or thyroiditis.
• High iodine intake.

Possible causes of hyperthyroidism

In addition, there are genetic factors that may predispose to this disease, as well as receiving radiation therapy in the neck area to treat the cancer. Pregnancy also poses an increased risk for transient hyperthyroidism, as there is an increase in the body's hormones. If this thyroid pathology during pregnancy is not treated correctly, there will be a risk of premature delivery and low birth weight.

Diagnosis and treatment of hyperthyroidism

The fundamental test for the diagnosis of hyperthyroidism is a blood test where the levels of the hormones T3, T4 and TSH are evaluated. However, attention should be paid to whether biotin is being taken as a supplement, as it could alter the results.

In the event that the results of the blood test show a decrease in the amount of TSH in the blood, as well as an increase in T3 and/or T4, then there is suspicion of hyperthyroidism. Therefore, it may be necessary to perform a radioiodine uptake test and radioiodine scan to determine the cause of hyperthyroidism:

• If the thyroid gland accumulates large amounts of radioactive iodine, it means that the gland secretes too much thioridea hormone. In this case, the possible cause of hyperthyroidism would be Graves' disease or overactive thyroid nodules.
• If the thyroid gland does not accumulate radioactive iodine, then it could be hyperthyroidism due to inflammation of the gland.

Tests for hyperthyroidism

Another complementary test in the diagnosis of hyperthyroidism could be to perform an ultrasound scan to detect possible nodules in the gland.

Depending on the cause of the hyperthyroidism, as well as the age and health status, the specialist will establish the best treatment option. There are anti-thyroid drugs (methimazole) that block the activity of the thyroid gland, beta-blockers that reduce the symptoms associated with the pathology, administration of radioactive iodine or surgery to remove the thyroid gland(thyroidectomy).

Hyperthyroidism and fertility

Excessive production of thyroid hormones by the thyroid gland has effects on general health and well-being, so it can also affect fertility in both men and women.

Listed below are the adverse effects of an overactive thyroid gland on fertility.

Female Fertility

The purpose of female sex hormones, such as progesterone and estrogens, is to control the proper functioning of the ovaries and follicular maturation. These hormones are interrelated with thyroid hormones.

For this reason, any thyroid alteration directly affects the functioning of the menstrual cycle and, therefore, hyperthyroidism has repercussions on a woman's fertility. It is also possible that the embryo implantation process may be altered, since thyroid hormones could negatively influence uterine receptivity and embryo implantation capacity.

Relationship between hyperthyroidism and female fertility

In addition, it has been shown that there is an increased risk of certain complications in the event of pregnancy. Some of them are:

• Miscarriage
• Preeclampsia.

In the case of women with untreated hyperthyroidism during gestation, they could jeopardize fetal development.

Male Fertility

Hyperthyroidism in males has an impact on their reproductive system, leading to an alteration in testicular function and, therefore, in sperm production. This would cause a decrease in seminal quality, leading to fertility problems in men.

In addition, excess thyroid hormones in men can cause a lowered libido, as well as erectile dysfunction.

It should be noted that treatments for hyperthyroidism, such as the use of certain drugs, surgery or radioiodine therapy, can cause temporary infertility in men.

FAQs from users

Can I get a hysterosalpingogram if I have hyperthyroidism?

Hysterosalpingography is a gynecological imaging study that is performed with an iodinated contrast substance, so the administration of the same in patients with hyperthyroidism could complicate and aggravate this condition.

In these situations, a thorough study of thyroid function and a timely endocrinological consultation is recommended.

Does hyperthyroidism affect sperm morphology?

Elevated thyroid hormone levels can affect sperm maturation and formation (spermatogenesis) and sperm quality. In addition, the concentration of available free testosterone is reduced, increasing problems with sexual intercourse, e.g. premature ejaculation.
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¿Qué diferencias hay entre el hipertiroidismo primario y secundario?

Primary hyperthyroidism refers to an excessive production of thyroid hormones by the thyroid gland.

On the other hand, secondary hyperthyroidism is referred to when the reason for the excess of thyroid hormones is due to an alteration in the pituitary gland.

Suggested for you

Hyperthyroidism is a cause of endocrine-related infertility. If you want to know all the details about it, you can access this link: Female infertility due to an endocrine-ovarian factor.

If you would like to know more information about thyroid disorders that affect fertility, we recommend reading this article: Female infertility due to thyroid gland problems.