In the 1960’s general practitioners (there were no family medicine specialists then) knew that empirically that putting women on thyroid medication helped reproductive function. Interestingly, thyroid medications were sold over the counter in the 1960’s. Soon after this, the FDA recalled the non-prescriptive drugs into prescriptive drugs categories and then required a blood test before patients could be medicated. Dr. Steven Langer, a family physician that’s published several books on the topic of infertility and thyroid related illnesses suggests that the TSH (thyroid stimulating hormone) levels must be assessed.

In addition, medical databases, such as PubMed (a service of the U.S. National Library of Medicine and the National Institutes of Health) have more and more research papers being published about “sub-clinical” hypothyroidism and infertility.

What is sub-clinical hypothyroidism?
Sub-clinical hypothyroid is usually asymptomatic, in which free thyroxine (T4) is normal and the thyroid stimulating hormone (TSH) level is between 5 and 25 mU/L, or, if a thyrotropin-releasing hormone (TRH) test is conducted, there is a greater than normal elevation in TSH response.

The American Association of Clinical Endocrinologists (AACE) in 2001 released a statement that said: "Even though a TSH level between 3.0 and 5.0 mU/ml is in the normal range, it should be considered suspect since it may signal a case of evolving thyroid underactivity”.

Some practitioners believe that levels above 2 are evidence of developing hypothyroidism.

Here are some simple steps to follow if you are suffering with infertility:

  • Ask your doctor to test TSH (thyroid stimulating hormone), T4 and T3.
  • Get a copy of the results and don’t accept “the results are normal”.
  • Normal range for TSH is approximately 0.5 to 5.5, but some endocrinologists believe that a Women's woman with suspected thyroid disease may have difficulty getting pregnant and/or maintaining a pregnancy at a TSH higher than 2.0.
  • If your TSH is "high-normal" and/or you had elevated antibodies, and your doctor is not willing to treat you, find a doctor or endocrinologist who has a good success rate working with thyroid-related infertility.

A naturopathic doctor can also run these tests for you, however there is a charge for the lab tests as they are not covered under O.H.I.P in Ontario.

In women with severe hypothyroidism, the level of a pituitary hormone called prolactin may also be increased, causing milk production (galactorrhea) unrelated to pregnancy and childbirth. The high prolactin level may prevent normal ovulation, causing decreased fertility, sometimes with irregular or absent menses.

How to choose the right naturopath
Seeking the care of a naturopathic doctor, with a track record in infertility using diet, supplementation, and acupuncture may also be helpful with or without conventional thyroid medication. Make sure that he or she has experience with infertility and or visit the OAND.org for information about his or her practicing in an area close to you.

George Tardik B.Sc.(hon), RHN, RNCP, (ND cand.) has been practicing nutrition for 10 years. He is a fourth year intern at the Canadian College of Naturopathic medicine’s RSNC clinic. He’s been featured on CBC’s Newsworld, Marketplace and Sports Journal. George specializes in metabolism, weight-loss, diabetes and sports nutrition. He practices out of Nature's Source. For booking appointments, please call 416.242.8500.