There are many reasons for male infertility such as hormonal imbalances, physical, psychological or behavioral problems. Thyroid hormones, previously thought not to affect male fertility, are now being recognized as having an important role e.g. in sperm production4,5 The good news: Correction of these disorders may restore a man’s fertility.

The overactive thyroid

If your thyroid gland produces and releases excess thyroid hormones into the bloodstream you have hyperthyroidism. Men can develop hyper¬thyroidism for a number of reasons, including Graves’ disease, overmedication with thyroid hormones for treatment of hypothyroidism, too much iodine in the diet, thyroid nodules, or an inflamed thyroid gland (known as thyroiditis). By speeding up your body’s metabolism, hyperthyroidism may result in many different symptoms; some of them are often mistaken for simple nervousness or stress.6

Key symptoms of hyperthyroidism6

  • Nervousness
  • Irritability
  • Fast heart rate
  • Weight loss
  • Increased sensitivity to heat
  • Muscle weekness
  • Increased sweating
  • Trembling hands
  • Hair loss

If you are having fertility problems and at the same time some of the symptoms6 – it is unlikely you would develop all of them – you should bring up thyroid disease with your doctor, especially if you have a family history of thyroid disease.

The underactive thyroid

If your thyroid gland produces not enough thyroid hormones, you have thyroid deficiency, medically known as hypothyroidism. The most common causes of hypothyroidism are iodine deficiency and, where iodine deficiency is uncommon, Hashimoto’s disease, an autoimmune disease that progressively destroys your thyroid gland.7 Thyroid deficiency slows down your metabolism Poor thyroid function5 is often associated with reduced libido and erectile dysfunction; furthermore it has an adverse effect on the form and structure of sperm – all of which can give rise to infertility.

Key symptoms of hypothyroidism7

  • Fatigue
  • Mental fogginess
  • Poor concentration and memory
  • Depression
  • Increased sensitivity to cold
  • Weight gain
  • Constipation
  • Dry skin and hair
  • Brittle nails
  • Joint or muscle pain

If you are having fertility problems and at the same time some of the symptoms you should see your doctor and tell him/her about your symptoms.


  • 1– Poppe, K, Glinoer D, Tournaye H et al. Thyroid function and assisted reproduction. In: The Thyroid and Reproduction, METS Riga 2008. Georg Thieme Verlag
  • Stuttgart 2009; 33-38.
  • 2– American Thyroid Association. General Information (2012) Accessed October 2012.
  • 3– Healy DL, Trounson AO, Andersen AN. Female infertility: causes and treatment. Lancet 1994; 343:1539–1544.
  • 4– Meikle AW. The interrelationship between thyroid dysfunction and hypogonadism in men and boys. Thyroid 2004; 14 (Suppl 1): S17-S25.
  • 5– Krassas GE, Poppe K, Glinoer D (2010) Thyroid function and human reproductive health. Endocr.Rev. 2010 31:702-755.
  • 6– The American Thyroid Association (2012) Hyperthyroidism October 2012.
  • 7– The American Thyroid Association (2012) Hypothyroidism Brochure. Accessed October 2012.
  • 8– Bercovici JP. Menstrual irregularities and thyroid diseases. Feuillets de biologie 2000; 74: 1063-1070.
  • 9– Vanderpump MPJ, Tunbridge WMG, French JM et al. The incidence of thyroid disorders in the community: A twenty-year follow-up of the Whickham Survey. Clin
  • Endocrinol 1995; 43: 55-69.
  • 10– Green BB, Weiss NS, Daling JR. Risk of ovulatory infertility in relation to body weight. Fertility and Sterility 1988; 50 (5): 721-726.
  • 11– The Hormone Foundation’s Patient Guide to the Management of Maternal Hypothyroidism Before, During, and After Pregnancy. De Groot LJ, Stagnaro-Green A,
  • Vigersky R, The Hormone Foundation 2007
  • Accessed October 2012.
  • 12– Grassi G, Balsamo A, Ansaldi C et al. Thyroid autoimmunity and infertility. Gynecol Endocrinol 2001; 15: 389–396.
  • 13– Beyond Infertility. Polycystic Ovary Syndrome (PCOS). U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES. National Institutes of Health; Eunice Kennedy
  • Shriver National Institute of Child Health and Human Development 2008
  • Accessed October 2012.
  • 14– De Groot L, Abalovich M, Alexander EK, Amino N, Barbour L et al. Management of Thyroid Dysfunction during Pregnancy and Postpartum: An Endocrine Society

  • Clinical Practice Guideline. J Clin Endocrinol Metab 2012; 97 (8): 2543-2565.