Hypothyroidism, or underactive thyroid, may affect up to 3 percent of pregnant women in the United States. Now, findings show that this condition is one of the most common causes of miscarriage among would-be mothers, according to a new study published in the Journal of Obstetrics and Gynecology. But diagnosing and treating the illness could help expecting moms avoid this and other complications, such as stillbirth and low birth weight, Fox News reports.
Thyroid disease occurs when the thyroid, a butterfly-shaped gland located at the front of the neck that controls almost all cells in the body, ceases to operate properly. The thyroid gland regulates metabolism and ensures that organs run efficiently. In addition, the gland is also very important for reproductive function, including egg production and fetal development during a woman’s pregnancy.
Experts estimate that between 10 and 15 percent of pregnancies will end in miscarriage for women who know they are pregnant. Thyroid dysfunction, an autoimmune disorder, is one of the most common causes of this problem. But doctors miss the culprit in 70 percent of mothers-to-be.
In addition, findings show that thyroid antibodies, which develop when the immune system targets thyroid-specific proteins (a hallmark of many types of thyroid disease), also increase not only the risk of miscarriage but also stillbirth, premature birth and low birth weight.
“Thyroid disease is a very subtle diagnosis—it’s not black-and-white,” said Prudence Hall, MD, founder of The Hall Center in Santa Monica, California, who commented on the study. Hall noted that many doctors test only for the hormone TSH when they’re screening pregnant women for thyroid issues. But other hormones, such as T3, T4, reverse T3 and thyroid antibodies, could also signal the disorder. (Although there are reference ranges for what constitutes normal amounts of thyroid hormone, many doctors disagree on what level is optimal for women.)
While study authors said they aren’t sure what percentage of miscarriages are caused by thyroid problems, the researchers theorized that the number is significant. But the good news is that thyroid dysfunction can be treated with medications before and during pregnancy to help lower this risk.
Still, some doctors stress that finding the root of the problem is the best way to reverse pregnant women’s thyroid issues.
To learn more about thyroid disease and its treatment, click here.