The Guidelines were the result of a multi-year effort by a task force, led by the American Thyroid Association (ATA), and included experts from the thyroid, obstetrics, gynecology and midwifery communities. The final Guidelines were approved by the ATA Board of Directors and officially endorsed by the American Association of Clinical Endocrinologists (AACE), British Thyroid Association (BTA), Endocrine Society of Australia (ESA), European Association of Nuclear Medicine (EANM), European Thyroid Association (ETA), Italian Association of Clinical Endocrinologists (AME), Korean Thyroid Association (KTA), and the Latin American Thyroid Society (LATS).
The key findings of "Thyroid Disease During Pregnancy and Postpartum: Guidelines for Diagnosis and Management from the American Thyroid Association" are summarized in the following series of articles.
- The Effects of Pregnancy on the Thyroid and TSH Levels
- Hypothyroidism, Hashimoto's Disease and Pregnancy
- Thyrotoxicosis and Hyperthyroidism in Pregnancy
- Graves' Disease and Pregnancy
- Postpartum Thyrotoxicosis / Hyperthyroidism
- Iodine and Pregnancy
- Postpartum Thyrotoxicosis / Hyperthyroidism
- Thyroid Antibodies, Miscarriage, Recurrent Pregnancy Loss, In-Vitro Fertilization and Fertility
- Thyroid Nodules and Thyroid Cancer in Pregnancy
- Postpartum Thyroiditis
- Thyroid Screening of All Pregnant Women
Some Concerns from the Advocacy PerspectiveWhile more up-to-date guidelines for the diagnosis and treatment of thyroid disease during and after pregnancy are welcome, there are concerns for women that need to be raised.
First, despite recognizing that, as the Guidelines authors stated, "...pregnancy is a stress test for the thyroid, resulting in hypothyroidism in women with limited thyroidal reserve or iodine deficiency, and postpartum thyroiditis in women with underlying Hashimoto's disease who were euthyroid prior to conception,", and demonstrating the risks to the pregnancy, the Guidelines do not recommend universal screening for hypothyroidism, iodine deficiency, or thyroid antibodies.
Second, the Guidelines recommended only oral levothyroxine (i.e., Synthroid, Levoxyl, Levothroid) for treating hypothyroidism during pregnancy. According to the Guidelines, it is "strongly recommended not to use other thyroid preparations, such as T3 or natural desiccated thyroid drugs." The Guidelines did not, however, include any citations or explanation regarding this recommendation, and when I queried lead author Alex Stagnaro-Green, MD regarding the situation of women who are well-maintained on a T3 or natural desiccated thyroid treatment, Dr. Stagnaro-Green only stated that "T4 can cross the placenta, but levels of T3 that cross are very low, therefore T3 only, combined T4/T3 and desiccated thyroid are all not recommended for women attempting pregnancy or who are pregnant." This means that the millions of women who are on thyroid hormone replacement that includes natural or synthetic T3 -- and who may not tolerate other forms of thyroid treatment -- may face resistance from their physicians, or may not be in a position to obtain treatment that is optimal for them.
Third, despite the established need for iodine in pregnant women, and the fact that women of childbearing age are the Americans most likely to have low iodine levels, testing for iodine deficiency, or counseling regarding the need for iodine are not regularly part of preconception evaluations, or doctor's visits during early pregnancy.
Fourth, despite the fact that the Guidelines said that there is a significantly decreased rate of pregnancy loss and preterm labor in women who are positive for Thyroid peroxidase antibodies (TPOAb) who are treated with levothyroxine, the Guidelines state that there is insufficient evidence to recommend for or against screening all women for thyroid antibodies in the first trimester of pregnancy.
Fifth, there is still no agreement regarding universal thyroid screening of women during the first trimester of pregnancy, and the Guidelines state that the evidence in support of universal screening is insufficient.
Given the many risks that undiagnosed/untreated/insufficiently treated thyroid disease pose to the pregnancy itself (miscarriage, preterm labor, stillbirth), and to the baby after birth (cognitive defects, mental retardation), the Guidelines may be doing a disservice to women who want to have a healthy pregnancy and baby. The Guidelines also put the burden on women who have risk factors but no overt thyroid disease to seek out and push for screening and evaluation on their own. There is also the concern that endocrinologists and obstetricians are not current on the guidelines. Many of them are not knowledgeable enough to safely manage a women with thyroid disease during pregnancy, and they are not aware of the new guidelines, which again puts the burden on women themselves to insist on careful and regular testing, and proper management and treatment.
What Should Women Do?From the patient advocacy perspective, here are some additional recommendations.
- If you are a woman who is at higher risk for thyroid problems, you could benefit from screening tests done prior to conception. Those who are at high risk for thyroid disease during pregnancy include women:
- with a personal history of thyroid dysfunction and/or thyroid surgery
- with a family history of thyroid disease
- with a goiter
- with thyroid antibodies
- with symptoms or clinical signs that may suggest hypothyroidism
- with type I diabetes
- with a history of either miscarriage or preterm delivery
- with other autoimmune disorders that are often linked to autoimmune thyroid problems, such as: vitiligo, adrenal insufficiency, hypoparathyroidism, atrophic gastritis, pernicious anemia, systemic sclerosis, systemic lupus erythematosus and Sjogren's syndrome
- with infertility
- who have previously received radiation to the head or neck area as a cancer treatment, or who have had multiple dental x-rays
- who are morbidly obese, which is defined as a body mass index (BMI) of over 40, or a body weight that is 20% or more over ideal body weight
- who are age 30 or older
- who have been treated with amiodarone (Cordarone) for heart rhythm irregularities
- who have been treated with lithium
- who, in the previous six weeks, have been exposed to iodine in a medical test contrast agent
- Women who are well-maintained on a hypothyroidism medication that includes T3 should talk to their physician before getting pregnant, to agree on a plan for thyroid hormone replacement during pregnancy.
- Women should ensure that their prenatal vitamins contain the recommended level of iodine. More education of endocrinologists, obstetricians, family doctors, and midwives also needs to take place to emphasize the importance of iodine nutrition during and after pregnancy.
- Women who are positive for thyroid peroxidase antibodies (TPOAb) may want to speak to their physicians about treatment, given the evidence of improved pregnancy outcomes.
- Finally, even though the Guidelines state there is insufficient evidence to recommend universal screening, that is "medical-speak" that is really talking about cost-benefit analysis. Meanwhile, the fact that there are demonstrable benefits to detecting and treating thyroid dysfunction during pregnancy, and universal thyroid screening in early pregnancy, is cold comfort to women who may lose a pregnancy, or whose children may suffer lifelong after effects of an undetected/untreated thyroid condition.
Stagnaro-Green, Alex, et. al. "Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and Postpartum." Thyroid. Volume 21, Number 10, 2011 (Online)