Thyroid Health and Your Risk of Miscarriage and Infertility
Updated: Sep 10, 2021

Its easy to overlook the glands and hormones outside of your reproductive system when you’re trying to get pregnant....
Unfortunately, without a healthy thyroid, pancreas or adrenal glands, your chances of conceiving and carrying to term are much reduced.
Your thyroid gland plays a crucial role in your menstrual cycle and your fertility, 1 in 8 women are diagnosed with thyroid problems during her lifetime, and about 10 % of women have an underactive thyroid gland, so this is a red flag we need to pay close attention to.
What’s more, many women have thyroid issues which go undiagnosed for years before they are finally find someone who is willing to pay attention and test more thoroughly. In fact - 79% of women who tested positive for thyroid antibodies had normal TSH levels!
Hypothyroidism is the most common thyroid problem – where the body doesn’t produce enough thyroid hormone. This can sometime be caused by a condition called Hashimotos thyroiditis, where your immune system attacks your thyroid gland, causing reduced levels of thyroid hormone.
Symptoms of an Underactive Thyroid
Weight gain
Fatigue
Hair loss and dry hair
Constipation
Fluid retention
Depression
Sensitivity to the cold,
Dry, pale skin
Brain fog, poor memory
Fertility Specific Thyroid Problems
Irregular periods
Delayed ovulation
Longer and Heavier menstrual bleeding
Infertility
Unsuccessful IVF
Implantation failure
Miscarriage
Short luteal phase
These are all signs your thyroid needs to be investigated thoroughly.
The test most often offered by your Doctor is simply- TSH, and occasionally freeT4. Unfortunately, this basic testing is not thorough enough.
These levels may be ‘in range’ as the reference for TSH and fT4 are still quite broad, which is why many women are sent away with the idea that their thyroid is perfectly ok... BUT, these basic tests don’t provide a full picture of thyroid health- for today and for your future health.
If you read the signs and symptoms above and tick many of the boxes, you’ll want to test your thyroid antibodies (TPOAb, TgAb, TRAb) and your reverse T3 also. This panel of testing may help you discover the cause of your symptoms and a frequently overlooked cause of fertility struggles, implantation failure and miscarriage.
Your Doctor is unlikely to recommend these tests for you if your TSH levels are normal…
But, if you have struggled with the above signs and symptoms, please persist! Discuss your concerns and organize testing with your Naturopath. The tests are not horribly expensive to pay for privately and this information is crucial to your wellness and particularly to your fertility.
If you have been trying to conceive and you have suffered miscarriage or suspect recurrent implantation failure, there is even more reason to dig deeper and be sure there are no issues with your thyroid antibodies.
Hypothyroidism and Infertility
Research shows that thyroid antibodies impair the implantation of embryos, as a result of endometrial receptivity defects. These changes can occur even when the TSH, fT4 and fT4 are in ‘normal’ ranges. Research also shows that women who test positive for thyroid antibodies have a 2-4 fold increase in the risk of miscarriage.
The good news is, even if testing shows you do have concerns in your thyroid hormone production and antibodies, there are effective treatment options available to improve your results, your health and your chances of a full term, healthy pregnancy.
Keep an eye out for my next post where I’ll share some of my fave tips for healthy thyroid!
If you recognize many of the issues above, its time to take action! Make an appointment asap so we can get you back on track to feeling great and celebrating your baby news.
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