Thyroid Health & Your Fertility

What is the thyroid gland?

The thyroid is a small gland located in the neck that releases hormones vital to controlling the body’s metabolism. When functioning properly, it produces and regulates hormones in the bloodstream. Hormone imbalances caused by an overactive (hyperthyroidism) or underactive (hypothyroidism) thyroid gland can affect energy levels, weight and mood, but they can also affect your fertility.

If you’ve been struggling to conceive or have undergone fertility treatment in the past, you may be familiar with thyroid-stimulating hormone (TSH). It is part of the blood panel drawn at the beginning of your fertility treatments to ensure optimal levels for treatment and pregnancy. However, regular screening of thyroid hormone levels is not routine for people of reproductive age who aren’t experiencing symptoms associated with thyroid dysfunction.

Dr. Collin Smikle, Medical Director at Laurel Fertility Care, recently spoke with the Founder of Fertility Help Hub, Eloise Edington, about how the thyroid gland can affect fertility, optimal TSH levels and more.

Q&A with Dr. Collin Smikle

Q: What are the causes of an under or overactive thyroid? Is it hereditary?

A: There are times when it can be hereditary. For example, some people have Graves’ Disease, where you have what we’d call a hyperactive thyroid gland. In this case, the body starts making antibodies against the thyroid gland that lowers TSH levels that can cause some people to feel bouncy and energetic.

Q: What is an optimal TSH level for fertility?

A: In general, a normal range for TSH levels are around 3 to 3.5. If you’re trying to get pregnant or are looking at managing your thyroid hormones during pregnancy, you want a level between 1 and 2.4. Low levels can means you ma havd a hyperactive thyroid that we would have to address. High levels mean your thyroid activity is low.

Both affect the fetus as it develops, and both need to be managed because of the consequences it can have on a pregnancy. Low TSH levels can cause miscarriages, and high levels— especially further along in the pregnancy—can pass through the placenta and affect the fetus.x

Q: What are treatment options for an underactive or overactive thyroid?

A: From a dietary standpoint, there are things taken in naturally that can affect the thyroid gland. Iodine or iodized compounds can help to support the thyroid. Before iodized salt was as common as it is today, we had a lot more patients with thyroid symptoms. Most salts today have iodine in them, which can help manage the thyroid gland.

If you have hyperthyroidism, you have too much stimulation of the thyroid gland and we want to avoid iodized salts. You’re also going to want to avoid shellfish and other seafoods like kelp and sushi. Iodine supplements should also be avoided.

On the other hand, if you have hypothyroidism, you’d want to add more fish, iodized salts and/or supplements into your diet to help support the thyroid.

Q: Do you see patients help their thyroid through diet and supplements alone?

A: Yes, they can manage some symptoms if they are what we call borderline. Someone who is hypothyroid can make dietary changes that will help. If it’s too high, where we’re seeing TSH levels over 5, it’s unlikely that diet changes will be sufficient. You’d need to take medicines that help support that shift.

Q: Do you see a lot of patients with thyroid problems? Is this a common issue?

A: It has become more of a common issue, and we see that many patients have thyroid levels of around 2.5 to 3.

Over the last five to six years, we have noticed that you can have a higher risk of miscarriage for patients in that higher range. Organizations like the American College of Obstetricians and Gynecologists have begun to manage this more actively and have conducted research that showed that for those with a thyroid hormone between 1 and 2.4, the risk of miscarriage diminishes. That is the range that we try to keep patients in during the time that they’re trying to get pregnant.

Q: What if someone doesn’t have a thyroid?

A: Someone who has a goiter, meaning there is a growth on the thyroid, may end up having to have their thyroid gland removed. That patient could be managed using Synthroid.

If there is a cancerous or pre-cancerous lesion in the thyroid, this can also cause the thyroid to be removed.

These situations can be quite easily managed, because there isn’t anything being administered to the body from the thyroid to counteract.

Head to our Instagram profile to learn even more about thyroid health and fertility from Dr. Collin Smikle and watch the rest of this live discussion.

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