What to Know About The Thyroid Gland and Your Cycle
The best way to describe the thyroid gland is small, but mighty. 💪
The thyroid gland is found at the base of the front of your neck. But, weirdly enough, it plays a huge role in ovarian function and your overall reproductive health.
The thyroid gland produces two main hormones:
- T4 (aka Thyroxine): An inactive form of thyroid hormone produced directly by the thyroid gland
- T3 (aka Triiodothyronine): An active form of thyroid hormone produced by converting T4 into T3
Together, these two hormones regulate growth and development, metabolism, and body temperature. Dysfunctional thyroid glands can affect both males and females, however, it is 8 times more common in females than males. 🤯
Disturbances in the thyroid gland’s functioning can impact the menstrual cycle. Hypothyroidism and hyperthyroidism are examples of such disorders. In order to understand these two disorders better, we need to go into a quick science lesson on how the thyroid gland is controlled! ✍
How is the thyroid gland controlled?
The all mighty thyroid gland is controlled by another gland located at the base of the brain called the pituitary gland. Just like the thyroid gland, the pituitary gland is small, but even mightier. It not only regulates and controls both thyroid function and ovarian function, but also your adrenal glands, your kidneys and even breast milk production!
First the hypothalamus releases a hormone called thyrotropin-releasing hormone (TRH). This signals the pituitary gland to release a hormone called thyroid-stimulating hormone (TSH), which signals the body to produce more thyroid hormones (T3 and T4) when the body is running low.
In hypothyroidism, TSH levels are high since the body is trying to stimulate the thyroid gland to produce more thyroid hormones.
In hyperthyroidism, TSH levels are low since the body is trying to limit thyroid hormone production.
Unfortunately, it’s not well understood why thyroid function affects ovarian function. Some studies suggest that thyroid hormones work with follicle stimulating hormones to grow follicles. Follicles play an important role in egg development and ovulation. Therefore, without enough thyroid hormone, ovulation might be limited. Another side effect of this is a potential reduction in progesterone levels.* In hypothyroidism, this might mean that progesterone levels are low, causing irregular menstrual cycles. 😩
*Progesterone is the hormone responsible for thickening the uterine lining and preparing the uterus for pregnancy.
Other studies have looked at the relationship between thyroid hormones and the prolactin hormone. Prolactin is a hormone also released by the pituitary gland during pregnancy and after birth to stimulate the production of breast milk. 🍼 A high level of TRH is thought to cause high prolactin levels. This is thought to cause anovulation, meaning ovulation does not occur nor does a period.
Ultimately, what we do know is that irregular thyroid function can cause a variety of symptoms in the body including irregular menstrual cycles.
In hypothyroidism, the thyroid gland is underactive, meaning not enough thyroid hormones are produced.
Symptoms of this include: tiredness, weight gain, irregular menstrual cycles, heavy menstrual bleeding, increased sensitivity to cold, hoarse throat, constipation, puffy face, thinning hair, and enlarged thyroid gland. ✔
In many cases, hypothyroidism is caused by an autoimmune disease called Hashimoto’s Disease. In this disease, the body does not recognize its own thyroid hormones. As a result, an immune response is triggered, attacking those hormones. Typically, this can be treated and managed with daily intake of oral, synthetic thyroid hormones.
In hyperthyroidism, the thyroid gland is overactive, meaning too much thyroid hormone is produced.
Symptoms of hyperthyroidism include unintentional weight loss even though appetite might increase, rapid heartbeat, sweating, tremors, sensitivity to heat, more frequent bowel movements, enlargement/swelling at base of neck, and changes in menstrual patterns.
One of the common causes of hyperthyroidism is another autoimmune disease called Grave’s Disease. Here, the immune system attacks the thyroid gland itself, causing it to overproduce thyroid hormones. A common treatment method is to take antithyroid medications, however, this is not a permanent fix. ✔
People with Thyroid disease can go through menopause earlier which can affect their chances of getting pregnant.
If you find yourself having any combination of the symptoms we mentioned, it’s a good idea to address it with your doctor! This is especially important if you’re on the pill or are thinking about going on it. 🤔
Some studies have found that oral contraceptives can interfere with the absorption of thyroid hormone replacement pills that are used to treat hypothyroidism. This is especially a concern for those taking the combination pill that contains estrogen as well. Taking the two pills together might make it hard for the intestine to actually absorb the dose of thyroid hormones. So, it’s best to take the birth control pill at least two hours after the thyroid pill!!
Our Final Thoughts
If there’s one thing to take away from this blog, it’s to track your symptoms! For starters, you can use the Aavia app to track things such as physical pain, tiredness, mood, and most importantly menstrual flow. Gathering this data on your body can help you and your physician to work out whether or not you have any abnormalities in your body. Download the app for free today on the IOS app store!💜