January is Thyroid Awareness Month.
But actually, it feels like that every month over here in my little corner of the internet because I so heavily emphasize getting it checked with nearly all of my clients.
It’s because the health of your thyroid plays a significant role in your ability to get pregnant and your ability to sustain a pregnancy.
Your thyroid is a butterfly-shaped gland located in front of your throat and releases thyroid hormones that serves various functions throughout the body.
Nearly every single cell uses thyroid hormone to help with metabolism (processing nutrients and energy). Your thyroid can also be described as the thermostat of the body due to its role in controlling your temp.
Your thyroid is involved in:
temperature regulation
heart rate
nutrient metabolism
brain function
menstrual cycles
growth and development (for you always and for your baby while pregnant)
…among many more roles!
I’ll be focusing on the roles your thyroid plays in menstrual cycles and pregnancy and what can happen when there are disruption in thyroid function.
But before we get into that, I’ll go over how the thyroid works (important to discuss how it works under normal circumstances so you better understand what’s going on when it’s not working properly).
How the thyroid works
Your brain and thyroid communicate via the HPT axis or hypothalamus-pituitary-thyroid axis). The hypothalamus released TRH (thyrotropin-releasing hormone) that stimulates the pituitary gland.
The pituitary gland then releases TSH (thyroid-stimulating hormone) that stimulates the thyroid to release T3 (20%) and T4 (80%) (and calcitonin but we’re skipping over that part). T3 is much more potent than T4 and is considered the active form of thyroid hormone.
T3 and T4 then travel throughout the body assisting cells in regulating their metabolism (among the many other roles listed above). Cells can also convert T4 to T3 or reverse T3 (the inactive form of thyroid hormone) depending on needs.
When concentrations of T3 and T4 in your bloodstream reach a certain level or threshold, they create a negative feedback loop to your brain. This shuts off the release of TRH, which then shuts down the release of TSH, decreasing the stimulation of your thyroid. Normal stimulation resumes again once T3 and T4 levels decrease.
This is a “picture perfect” version of how your thyroid (should) function. Of course, things don’t always work out that way!
Thyroid’s role in menstrual cycles
The thyroid’s role in menstrual cycles is complex…to say the least. I’ve tried to simplify it here but know this is surface level. It goes much deeper than this and there’s still so much we don’t know.
Thyroid hormone plays a role in how sex hormones are made, transported, and excreted. By sex hormones we’re talking major players like estradiol and testosterone.
Thyroid hormone also plays a role in controlling other hormones that indirectly influence your cycle. So, thyroid hormone can influence factors such as the length between periods (whether short or long or if your period shows up at all) to how light or heavy your period flow is.
Thyroid hormones also act directly on ovarian cells. One role is to help facilitate the recruitment and maturation of follicles (very important as those are the beginning stages of ovulation).
So, when there are disruptions in thyroid function, it can have several downstream impacts on your cycle, which can ultimately impair your fertility.
That’s where taking care of your thyroid is SO important when it comes to preconception health and at the core of what I look into with clients who are struggling to get pregnant.
Thyroid’s role in pregnancy
There is an increased demand for thyroid hormone during pregnancy.
In the early weeks of pregnancy (up to week 12), the fetus is dependent on your thyroid’s ability to provide it necessary hormones.
By week 12, the fetus is starting to make its own thyroid hormones but still not enough until about weeks 18-20 (meaning still heavily dependent on you).
Most importantly, the fetus needs thyroid hormone to have proper brain and nervous system development. (Remember above when I mentioned that every cell in the body uses thyroid hormone to function).
Your thyroid needs to be able to not only provide you enough hormone but the fetus, too (and have that amount of hormone be enough but not too much!
Bottom line: the function of your thyroid is crucial to sustaining a healthy pregnancy!
This month we’ll be getting into the ways to support your thyroid and what labs to ask for to assess function!
If you’re wanting support for your thyroid while TTC, apply to work with me here!
