Between 10 and 15 percent of pregnancies will end in miscarriage in women who know they are pregnant and although the pain they endure is crystal clear, the cause of the miscarriage isn’t always known.
Yet experts warn that Western medicine is missing something: That thyroid dysfunction, which is missed in 70 percent of women, is one of the most common causes of miscarriage, said Dr. Prudence Hall, founder of The Hall Center in Santa Monica, California..
Although all types of thyroid dysfunction may be to blame, hypothyroidism, or underactive thyroid, is the most common and may affect up to 3 percent of pregnant women, studies show.
“We don’t know exactly how many women are going to miscarry due to low thyroid but it’s significant,” Hall said.
Autoimmune thyroid disease, which is the most common autoimmune disorder in women of childbearing age and affects between 5 to 15 percent of women, according to a study in the Journal of Obstetrics and Gynaecology, can also be a cause of miscarriage.
Not only that but “most all thyroid dysfunction is autoimmune in nature,” said Dr. Amy Myers, author of “The Autoimmune Solution,” and “The Thyroid Connection.”
Thyroid antibodies, which develop when the immune system targets thyroid-specific proteins, have been shown to increase the risk for miscarriage and stillbirth as well as premature birth and low birth weight, Myers said.
Plus, women with mild hypothyroidism and thyroid autoimmunity are at increased risk for miscarriage, according to a study in the journal Thyroid.
What’s more, women with hypothyroidism who took thyroid hormone replacement therapy and who had thyroid-stimulating hormone (TSH) levels of about 2.5mU/L in early pregnancy had an increased risk of miscarriage, according to study in the Journal of Clinical Endocrinology & Metabolism.
A powerhouse gland
The thyroid is a butterfly-shaped gland located on the front of the neck that secretes thyroid hormones, which circulate throughout the blood and affect nearly every cell in the body. The thyroid gland is like the command center of the body, regulating metabolism and making sure your organs run efficiently.
The thyroid is also important for reproductive function, and can affect egg production and the development of the fetus. It also helps the baby’s brain to develop and is responsible for the formation of the baby’s own thyroid gland.
Just like the other hormones in the body, thyroid hormones do not work in isolation, so when the thyroid hormones are unbalanced, the other hormones needed for a healthy pregnancy will be too.
“All our hormones are working together all the time,” Myers said.
A missed opportunity
If diagnosing and treating thyroid dysfunction could potentially prevent more miscarriages, it would seem advantageous for more doctors to screen their patients before they conceive.
The problem however, lies in how a diagnosis is made in the first place.
“Thyroid disease is a very subtle diagnose— it’s not black and white,” Hall said.
For starters, between 40 and 50 percent of women who are screened with only a blood test will not be identified. Many doctors may only test TSH, when it’s necessary to also test the other thyroid hormones: free T3, free T4, and reverse T3 and the thyroid antibodies, thyroid peroxidase and thyroglobulin, Myers said.
Although there are reference ranges, experts agree that what is considered normal, is not optimal.
Doctors should also ask women about their symptoms, which are as important as the blood tests.
“Symptoms, in my opinion, should always outweigh lab tests,” Myers said.
Women should also have their reflexes tested, since reflexes are very slow when the thyroid is underactive.
Hall recommends every woman take between 5 and 10 milligrams of iodine before and during pregnancy. Not only is iodine deficiency one cause of thyroid dysfunction, but it helps the thyroid gland work better and studies show it can also increase the baby’s brain development and IQ.
Thyroid dysfunction can also be familial, due to heavy metal toxicity, an infection, leaky gut syndrome or gluten sensitivity.
Although diagnosing thyroid dysfunction may be the missing link when it comes to preventing miscarriage, and treating it with medication is an option, finding the root cause can potentially reverse it.
“This is certainly a piece of the puzzle, but why is the woman getting thyroid dysfunction in the first place?” Myers said.
Julie Revelant is a health journalist and a consultant who provides content marketing and copywriting services for the healthcare industry. She's also a mom of two. Learn more about Julie at revelantwriting.com.