Thyroid and infertility in women

Dr Hina Naveed

By Dr Hina Naveed

Hina is the Marketing Manager at the Middle East Medical Portal. She is an experienced Pharmacist, writer, and speaker. Hina lives in the United Arab Emirates.

Thyroid and infertility in women

Thyroid scan

According to a Harvard Medical School study, having even a slightly underactive thyroid may interfere with a woman’s ability to get pregnant. More than a quarter of the women in the study who had unexplained infertility showed signs of a thyroid gland performing at low-normal levels. Those women were about twice as likely to have higher levels of thyroid-stimulating hormone (TSH) than women who did not conceive due to known issues with their male partner’s sperm count.

Women are more likely than men to have thyroid disease and one in eight women will develop thyroid problems during her lifetime.

Thyroid informationIn women, thyroid disease can cause:

  • Problems with your menstrual period: Your thyroid helps control your menstrual cycle. Too much or too little thyroid hormone can make your periods very light, heavy, or irregular. Thyroid disease also can cause your periods to stop for several months or longer, a condition called amenorrhea. If your body’s immune system causes thyroid disease, other glands, including your ovaries, may be involved. This can lead to early menopause (before age 40).
  • Problems getting pregnant: When thyroid disease affects the menstrual cycle, it also affects ovulation. This can make it harder for you to get pregnant.
  • Problems during pregnancy: Thyroid problems during pregnancy can cause health problems for the mother and the baby.

Sometimes, symptoms of thyroid problems are mistaken for menopause symptoms. Thyroid disease, especially hypothyroidism, is more likely to develop after menopause.

Both hyperthyroidism and hypothyroidism can make it harder for you to get pregnant. This is because problems with the thyroid hormone can upset the balance of the hormones that cause ovulation. Hypothyroidism can also cause your body to make more prolactin, the hormone that tells your body to make breastmilk. Too much prolactin can prevent ovulation.

Hyperthyroidism that is not treated with medicine during pregnancy can cause:

  • Premature birth (birth of the baby before 39 to 40 weeks, or full-term).
  • Preeclampsia, a serious condition starting after 20 weeks of pregnancy. Preeclampsia causes high blood pressure and problems with the kidneys and other organs. The only cure for preeclampsia is childbirth.
  • Thyroid storm (sudden, severe worsening of symptoms).
  • Fast heart rate in the newborn, which can lead to heart failure, poor weight gain, or an enlarged thyroid that can make it hard to breathe.
  • Low birth weight (smaller than 5 pounds).
  • Miscarriage.

Hypothyroidism that is not treated with medicine during pregnancy can cause:

  • Anaemia (lower than normal number of healthy red blood cells).
  • Preeclampsia.
  • Low birth weight (smaller than 5 pounds).
  • Miscarriage.
  • Stillbirth.
  • Problems with the baby’s growth and brain development.

The epidemiology of thyroid diseases in the Arab world: A systematic review

Westernization and nutrition transition in Arab world have increased the burden of adenocarcinomas, including thyroid cancer. This review aims to present the aggregated burden, risk factors and prognosis of various thyroid diseases prevalent in Arab countries.

An electronic databases search was conducted using PubMed in addition to searching of accessible local journals in Arab world, using keywords and terms like epidemiology, burden, odds, risks, etc. After applying exclusion and inclusion criteria, 21 articles were selected to include in this review.

The review showed that the prevalence of different types of thyroid disease varied between the reported studies in Arab world ranging from 6.18 to 47.34% prevalence of goiter reported by several studies conducted in Arab world, such as Egypt, Algeria and Bahrain with 25.25, 86 and 1.7%, respectively.

Gender, dietary factors, iodine deficiency, family history, diabetes and x-ray radiation were reported as risk factors associated with different type of thyroid diseases. The most prevalence of thyroid disease was concluded to be thyroid lesions which varied in different regions of Arab and the burden of thyroid cancer is very high and very common in different Arab region, and further longitudinal studies are still needed to investigate the prognosis and determinants of these thyroid diseases in the Arab world.

‘Secondary infertility’ rates in the UAE are among the highest in the world, which is causing a massive decline in the country’s population and the population will continue to rapidly drop if changes are not made, warn doctors.

There is a significant drop in the number of children born in the UAE and this has a huge impact on the total population, and increasing the case of IVF. The number of births in the UAE is anticipated to drop to 1.66 per couple from 2020-2025. According to the Dubai Health Authority (DHA), around 50 per cent of the women face infertility issues. Statistics also reveal that women in Dubai seeking treatment per year could nearly double, from 5,975 in 2015 to 9,139 by 2030.

Hashimoto’s thyroiditis and PCOS: Is There a Connection?

Autoimmune thyroiditis, Hashimoto's disease. 3D illustration showing antibodies attacking thyroid gland
Hashimoto’s disease: Illustration showing antibodies attacking thyroid gland

If you have been diagnosed with polycystic ovary syndrome, or PCOS, you are well aware that one the tell-tale sign is that your hormone levels are out of balance. Common symptoms include menstrual irregularity, problematic acne, and excessive hair growth. You may also struggle with your weight due to the disruptions that PCOS causes to your metabolism, and you may have difficulty getting pregnant.

Hashimoto’s thyroiditis, an autoimmune hypothyroid condition in which the body’s immune system attacks the thyroid—is three times more common in women with PCOS than in women without it.

If you are a woman with PCOS, your body may be producing too much androgen. Androgens are a class of male sex hormones, in particular, testosterone, that are found in smaller but necessary levels in women too. Higher levels of androgen may interfere with a woman’s ability to get pregnant; for this reason, many women with PCOS struggle with infertility.

Surprisingly, the researchers found that high levels of androgen are less common in patients who have both conditions: Hashimoto’s thyroiditis and PCOS. This hormone pattern was confirmed even when looking at testosterone alone–an increased testosterone level is not found in patients with both conditions.

Ovaries in thyroid hormone

In the presence of hypothyroidism, ovarian morphology becomes polycystic. Hence, thyroid disorders are one of the exclusion criteria before making a diagnosis of PCOS in any women.
Rise in thyrotropin-releasing hormone (TRH) in primary hypothyroidism leads to increased prolactin and thyroid stimulating hormone (TSH). Prolactin contributes toward polycystic ovarian morphology by inhibiting ovulation as a result of the change in the ratio of follicle stimulating hormone (FSH) and luteinizing hormone and increased dehydroepiandrosterone from the adrenal gland. Increased TSH also contributes due to its spill-over effect on FSH receptors. Increased collagen deposition in ovaries as a result of hypothyroidism has also been suggested.

Hypothyroidism, PCOS and sex hormone binding globulin

Now, there is something else that we need to consider. We know that women with POCS tend to have lower levels of SHBG. This is problematic because SHBG picks up free testosterone in the blood and helps to make it inactive. So, the less SHBG you have, the more testosterone you have to make your PCOS symptoms worse.

Here’s the thing, it is our thyroid hormones that increase the levels of SHBG. So, if you do have a sluggish thyroid, you will have a harder time getting your PCOS under control. Now that we know that there is this strong link, what should we do about it? Well, there are a couple of things. It’s really important that we all have our thyroid function monitored. My doctor runs blood tests every two years or so to monitor my general health and PCOS and thyroid function is included in this.

Treatment for thyroid disorders

If you suspect that you may have a thyroid disorder or your blood work shows an anomaly in your thyroid hormones, there is medical treatment available. Your doctor will guide you on this.

Diet and thyroid disorders

Healthy foodOnce again, we come back to the cornerstone of PCOS Diet Support. Your diet can impact on your thyroid health, as well as your PCOS. Here are some suggestions to support your thyroid function and improve your PCOS:

Avoid soy: Soy products contain phytoestrogens that have been shown to increase the risk of developing subclinical hypothyroidism. Soy can also cause delayed ovulation which is why I don’t recommend soy products as part of a good PCOS Diet.

Give up Gluten: There is a protein in gluten (gliadin) that is very similar in structure to a thyroid hormone. So, if you have a gluten sensitivity, your body not only attacks the gliadin, it can also attack your thyroid in an autoimmune response.

Avoid sugar: Research has shown that hypothyroidism can make insulin resistance worse. And, eating sugar or highly refined carbs causes your body to release more insulin. Remember that all of this insulin is also causing your ovaries to release more testosterone. So, by avoiding highly processed and sugary foods, you are managing your PCOS and supporting your thyroid function.

Conclusion

We’ve established that women with PCOS are 22.5% more likely to have some type of thyroid dysfunction. This can make our PCOS symptoms worse and much harder to manage.
I highly recommend that you have your thyroid levels checked at least every two years. Following a good PCOS diet will not only help to manage your PCOS, it will also support your thyroid health.

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