How does Thyroid affect Male Fertility ?

There are many causes for Male infertility and Thyroid function (or malfunction) seems to be one of them.

The thyroid gland affects almost all parts of the body and plays a major part in growth and development of the human body. The secretion of its hormones regulates the metabolism and ability to tolerate extreme temperatures, either heat or cold.

Thyroid hormones act on testis in many ways. Excessive or deficient thyroid hormones affect the testis function, including abnormalities in semen. Hyperthyroidism (excess of thyroid hormones) is usually associated with reduced semen volume and reduced sperm density, morphology and motility. Hypothyroidism (underactive thyroid hormones) results in low sperm count, poor semen quality, reduced testicular function and erectile dysfunction.

The positive side is that this can be treated and Hypothyroidism is reversible with hormone replacement therapy. The free testosterone concentrations which are reduced in men with primary Hypothyroidism can be normalized with this treatment. Also, for Hyperthyroidism, antithyroid medication, causing the thyroid to produce less hormones, radioactive iodine and surgery are also effective treatments to restore thyroid function to normal. Food items which are a good source of iodine are milk, cheese, poultry, eggs and seaweed. Vitamin sources such as Vitamin B, Zinc and Selenium are also beneficial in improving hormone levels and thyroid function.
However, too much iodine or vitamins in the body can be problematic. It is recommended that, before starting any treatment or adding supplements, you contact your doctor who will be able to recommend a required level of treatment to suit your body.
One of the most common causes of Hyperthyroidism in men is a condition known as Graves’ disease, where a healthy thyroid gland is mistakenly attacked by the immune system, which causes it to produce too much thyroid hormone. Also, consumption of too much iodine (either by medication containing iodine or from food and supplements) may result in overproduction of thyroid hormones.
On the other hand, a similar autoimmune disease occurs when the immune system mistakes normal parts of the body as “foreign invaders” and attacks them, blocking the TSH (thyroid stimulation hormone) receptor and destroying the thyroid tissue. This disease that usually causes Hypothyroidism is Hashimoto’s thyroiditis.

Some of the symptoms of an underactive thyroid in men are:

• Tiredness and fatigue
• Dry skin and brittle nails
• Feeling cold
• Depression
• Constipation
• Trouble with concentration
• Gaining weight
• Sore muscles

An overactive thyroid in men can cause some of the following symptoms:

• Swelling of the thyroid gland, called goiter
• Feeling very hot and sweaty
• Warm skin that may be itchy
• Anxiety or moodiness
• Hand tremors, or an irregular heartbeat or trouble with breathing even when you are at rest
• Weight loss
• Frequent and sometimes loose bowel movements
• Brittle hair or premature balding.

While studies are still under way to prove that male infertility can definitely be caused by thyroid malfunction, it is advisable that thyroid function tests should be part of the diagnostic workup if a man is found to be infertile.