When it comes to thyroid health, many people (including myself) underestimate the importance of this essential hormone until a problem is encountered. In fact, I was not even fully aware of everything the thyroid hormone does until my doctor had me take a blood test years ago to make sure everything was healthy. I was a college student in pharmacy school at the time; however, my studies didn’t quite cover the thyroid functions yet, and I was pretty unaware of just how significant thyroid health is and how much it contributes to the functions of everyday life. Fortunately, my thyroid turned out to be healthy, yet it is something I think about from time to time, and especially when I was pregnant with my boys. Pregnancy affects thyroid health in many ways because the body is already experiencing hormonal changes.
Sometimes lab values that signify thyroid health can be difficult to understand. It helps to know what exactly the thyroid is and how it works in the body. The thyroid gland releases the thyroid hormone which plays a role in many body functions, such as helping the body utilize energy and stay warm and keeping the organs working as they should. The major hormone secreted by the thyroid gland is called thyroxine, or T4. The “4” refers to the number of iodine atoms it contains. T4 is converted to T3 in the liver. T3 is the hormone that produces all the effects we see in the body, so this conversion is necessary.
If you ever had lab tests regarding your thyroid, you may encounter a value called “TSH.” TSH is short for “thyroid stimulating hormone”. This hormone almost works like a thermostat controlling a heater. If the body sees that too little T4 is being produced by the thyroid gland, TSH levels rise in an effort to “stimulate” T4. Hence, if TSH levels are coming back high in blood tests, it is because there is too little thyroid hormone. It helps to think that TSH and T4 operate in an inverse fashion. If TSH is high, thyroid hormone is low and the diagnosis is “underactive thyroid” or “hypothyroid.” If TSH is low, thyroid hormone is high and the diagnosis is “overactive thyroid” or “hyperthyroid.” Blood tests usually measure ALL values pertaining to the thyroid – including T4 and T3 – and can be a very clear way to see the whole picture if there is an issue, especially in pregnant women. Sometimes it is helpful to actually see the thyroid gland via a scan, as well.
Many conditions exist that affect thyroid health, but in this article, I will solely focus on underactive thyroid during pregnancy. Of equal importance is that lingering thyroid conditions that are left untreated prior to pregnancy could potentially make it difficult to conceive or carry the baby to term. An overactive or underactive thyroid could be one of those hidden factors that affect fertility and need to be explored further. If thyroid conditions are mild, symptoms are usually vague and mild, as well, making it even harder to differentiate problems. For instance, hypothyroidism can produce symptoms of fatigue, dry hair and skin, mild depression, heat intolerance, and constipation. These are all symptoms that could be easily overlooked or attributed to other lifestyle factors. I always recommend that women of child-bearing age who foresee pregnancy in the next several years get regular check-ups and blood work performed with their doctor. It is important to stay on top of your health and treat any issues even before you conceive.
When a woman becomes pregnant, the body will need adequate thyroid hormone to support her growing baby and for her own metabolic needs, too. The thyroid hormone is important for brain growth and other fetal metabolic development. In early stages of pregnancy, the baby will obtain its thyroid hormone from the mother. In later stages, the baby will start to make its own. However, the baby will still require iodine from the mother in order to supply its own. Many prenatal vitamins contain 150mcg of iodine, but the typical American diet usually contains enough iodine through the addition of iodized salt. Most table salt and the salt found in processed foods are iodized. Some “natural” salts – like Himalayan pink salt and sea salt – are not always iodized. Again, having to supplement with additional iodine is very rare – even if you do prefer the natural salts – and most likely, your prenatal vitamin already contains iodine.
Routine testing of the thyroid with otherwise healthy, pregnant women is still controversial. Usually, the clinician examines the woman’s history to see how necessary it is to evaluate her thyroid. Often, a personal history with a thyroid condition or even a close family history will precipitate the need for blood work. Both the American Thyroid Association guidelines and the Endocrine Society guidelines do not recommend universal screening; however, if there are any concerns whatsoever, it does not hurt to take a look.
If you do need to use thyroid medication while pregnant, find comfort in knowing that these types of medications (notably, levothyroxine) are usually very safe for both you and your baby. Levothyroxine is virtually the same as your natural thyroid hormone, so augmenting with this medication at the appropriate dose poses very little to no harm. If you have already been diagnosed with hypothyroidism prior to pregnancy and are already taking levothyroxine, it has been well documented that you may need to bump up your dose by as much as 30%. It is important to find the right dose with your doctor, and you may need several lab tests along the way in order to do this.
I am always an avid proponent of lifestyle interventions, no matter what the issue may be. Having to take a thyroid medication while trying to conceive or while pregnant may be of absolute necessity if you have been diagnosed with hypothyroidism, but other “natural” modifications can help ensure you have a healthy pregnancy and a healthy baby. A well-rounded diet loaded with organic fruits and vegetables can do wonders for anyone, but especially those who are pregnant, suffer from low thyroid, or both! I like well-rounded diets that contain some indulgences from time to time, too!
Sometimes people with very low thyroid levels have trouble absorbing nutrients. The thyroid hormone helps with metabolism all over the body, including the digestive tract. If your thyroid hormone is low, you may have trouble extracting nutrients from foods. Also, if you are pregnant, you may have aversions to certain foods or morning sickness which forces you to eat only crackers all day. If you are both pregnant and moderately/severely hypothyroid, you can see where nutrient deficiencies may add up quickly. Taking a good quality prenatal vitamin can help to supplement. Sometimes, blood work can test for specific deficiencies if you’re not sure where to begin. Vitamin B12, selenium, magnesium, and iron are all important to the hypothyroid, pregnant woman. Your doctor can assess whether further supplementation beyond a prenatal vitamin is needed, however I recommend that the majority of nutrients be obtained from good quality food sources. Focus on smoothies made from organic frozen fruits, foods with probiotics (like yogurt), and salads or bowls topped with vegetables, seeds, nuts, and creative seasonings.
It is also important to remember that your immune system is weakened when pregnant. Some viruses can trigger thyroid conditions and/or put the baby at risk for preterm labor. Always remember to wash your hands periodically throughout the day and especially after outings. It may look a little silly but wearing a face mask in congested areas (like airports, malls, etc.) can help a lot too.
If you are thinking about little ones now or down the road, I hope this article helped! Your thyroid plays such a significant role in your body that it may affect your fertility and pregnancy, even these things aren’t in your near future!
