New Guidelines Released Re: Thyroid Disease & Pregnancy

by Mary J. Shomon

In announcements this week by the American Thyroid Association, the endocrinology community has finally come around to recommending guidelines regarding hypothyroidism and pregnancy that I have been recommending for years to women, and that were included in my book Living Well With Hypothyroidism relesesed back in 2000, and in my recent Thyroid Guide to Fertility, Pregnancy and Breastfeeding Success.

There is no disagreement that a mother's thyroid function can have an impact on the outcome of a pregnancy and the development of her child. Endocrinologists have agreed for decades that overt hypothyroidism needs to be treated during pregnancy to prevent an adverse outcome for both mother and baby.

But the need for frequent testing during pregnancy, the likelihood of a need for increased thyroid hormone medication during pregnancy, and the risk of thyroid antibodies -- among other factors -- have been controversies and many physicians have refused to acknowledge these situations.

The American Thyroid Association (ATA) has, however, now come around to the position that there is a potential for an adverse outcome when a mother has subclinical hypothyroidism (where the T4 levels are normal, and TSH is slightly elevated) and when a mother has thyroid autoantibodies.

Bottom line? The ATA is now saying that even mild hypothyroidism can cause serious problems with the pregnancy, including premature birth or lower IQ in the baby.

This is a major departure, as until recently, many endocrinologists insisted that thyroid antibodies, or mild hypothyroidism had no impact on fertility, pregnancy, or the development of the baby.

According to the ATA Statement:

- Pregnant mothers with overt or subclinical hypothyroidism are at an increased risk for premature delivery.

- Pregnant mothers with detectable thyroid autoantibodies and normal thyroid function are at an increased risk for miscarriage and for postpartum thyroid disease including thyroiditis, hyperthyroidism (Graves’ Disease) and also hypothyroidism.

- The offspring of mothers with thyroid hormone deficiency or thyroid stimulating hormone elevation during pregnancy may be at risk of mild impairment in their intellectual function and motor skills.

- Pregnant women being treated with thyroid hormone replacement often require a 30-50% increase in their thyroid hormone dose.

The ATA is calling for more extensive research into the nature of these problems, as well as the need for expanded testing programs.

In the meantime, the ATA is calling for testing before pregnancy and in early pregnancy of women who are at high risk for thyroid disease. Those at risk include those who have had previous thyroid problems, those with previous or existing autoimmune disease, and those with thyroid and autoimmune conditions in the family.

And, among those women who are already diagnosed with hypothyroidism, they need more frequent testing to ensure that they are not subclinically hypothyroid, and to ensure proper dosage.

What Should You Do?

While the ATA and endocrinologists debate what research is necessary in the bigger picture, women who are contemplating pregnancy have options:

Women who are contemplating pregnancy -- even those without a personal or family history of thyroid or autoimmune disease -- should , as a precautionary measure, get a basic TSH test. This can be done through your doctor, or you can purchase a home test kit.

Any woman who has a personal or family history of thyroid or autoimmune disease -- should have her thyroid tested prior to becoming pregnant, and again within the first weeks of early pregnancy. She should be tested throughout the pregnant as often as symptoms might indicate, but at least once a trimester.

Any woman with a diagnosed thyroid condition should have her thyroid tested prior to becoming pregnant, and again within the first several weeks of early pregnancy. She should be tested frequently throughout the pregnancy, including several times in the first trimester, and throughout the pregnancy as often as clinical signs and symptoms might indicate, but at least once in each of the second and third trimesters.

Women contemplating pregnancy should make sure they start taking a prenatal vitamin that includes not only folic acid, but iodine, before becoming pregnant, and continue taking that vitamin throughout pregnancy. (Note, however, that women taking a prenatal vitamin with iron will need to be careful about separating the vitamins from their thyroid hormone by at least 3-4 hours at minimum, or othe iron may make the thyroid hormone less effective by interfering with absorption.)

Find out more information about the ATA Statement.

For information on getting pregnant, and having a safe, healthy pregnancy for both mother and baby, despite thyroid conditions, read the Thyroid Guide to Fertility, Pregnancy and Fertility Success.