Hold control (command on a Mac) and press the + key as many times as necessary to increase the font size.
Hold control (command on a Mac) and press the - key to reduce the font size. - hide

Graves' Disease and Pregnancy

Summarized by Susan E. Calico

A woman with Graves’ disease faces difficult choices when she considers pregnancy. Though the fetus is at far more risk than the mother, both may be temporarily or permanently affected by her condition and its treatments.

Unfortunately, there is no way to monitor or predict the effect on the fetus of any treatment given to the mother. The few studies on Graves’ pregnancies are so few and small that the results are inconclusive. Even after birth, neither infant appearance nor blood tests are conclusive predictors of the child’s future.

Risks of Pregnancy

The first precaution is to normalize the mother’s condition before conception. Women using anti-thyroid drugs should establish a stable maintenance dose of PTU. For women treated with surgery or radioactive iodine, replacement thyroid hormone dose should be stabilized. Waiting six months after radioactive iodine treatment to conceive minimizes the effects of the radiation on developing eggs.

But the child can be affected even when the mother’s Graves’ is well under control. No matter how long ago they were diagnosed and treated, most women with a history of Graves’ have measurable levels of thyroid-stimulating antibodies (TSAb, TBII and LATS) present in their blood.

These antibodies can cross over the placental barrier and cause Graves’ symptoms in the fetus. The symptoms – hyperthyroid, goiter, bulging eyes – usually disappear within a few months after birth, when the baby is no longer exposed to the antibodies. But in some, the symptoms linger for years or reoccur later in childhood. In these cases, the mother’s antibodies may have triggered Graves’ disease in the child.

Poorly Monitored Graves’

Because pregnancy “stirs up” the thyroid, even women who presumably have little of their thyroid left after radioactive iodine or surgery can’t rule out a hyperthyroid episode. The normal elevation of thyroid hormones in pregnancy can mask a recurrence for women with a history of Graves’. For this reason, close monitoring of fetal signs and maternal blood levels (every 2 to 4 weeks) is important.

Though neither synthetic replacement hormone nor the mother’s natural thyroid cross the placental barrier, too much or too little can have serious indirect affects on the fetus. Hypothyroidism (or undertreatment with replacement hormone) causes prolonged gestation and underdevelopment of the fetus.

Hyperthyroidism (or overmedication with replacement hormone) imperils both the mother and the fetus. These infants are more likely to die shortly before and after birth. Premature delivery is likely, though the infant will have fewer “preemie” problems because its development is accelerated by the excess thyroid hormones. And later on, the child may have shorter stature and subtle nervous-system defects. The mother risks the life-threatening thyroid storm, especially during labor and delivery.

Controlling Graves’ During Pregnancy

If Graves’ reoccurs or first occurs during pregnancy, the options are limited by the direct and indirect effects of many drugs on the fetus. Tapazole™ should be avoided during pregnancy and breastfeeding because it can suppress the infant’s thyroid, but PTU in similar doses has more moderate and less permanent effects. Dosage of PTU should be limited to less than 300 mg during the first and second trimester, PTU can usually be stopped during the third trimester as the natural suppression of the immune system during pregnancy causes a gradual remission of Graves’ symptoms. PTU is not concentrated in breast milk, so moderate doses of 200 mg or less are thought to have little effect on nursing infants.

Thyroid surgery is another option for controlling Graves’ during pregnancy. The surgery is usually performed in the second trimester to maximize fetal survival.

Management of Graves’ during pregnancy is complicated by the crossing-over of some thyroid-related medications to the fetus. Iodine treatment is the most dangerous of these, whether radioactive iodine or iodine drops (used to temporarily suppress the thyroid). After 10 weeks gestation, iodine passes easily to the fetus, with high rates of death; radioactive iodine results in destruction of the fetus’ thyroid and parathyroid, and sometimes chromosomal damage. Therefore, any treatment or testing with iodine during pregnancy should be strictly avoided.

Propranolol (beta blocker) can also affect the fetus and infant, suppressing heart rate, respiration and growth, and affecting the liver and glucose metabolism. Its use is avoided during pregnancy and breastfeeding.


“Hyperthyroidism is Pregnancy” by Dorothy R. Hollingsworth, published in Werner’s The Thyroid ed. Sidney H. Ingmar and Lewis E. Braverman, Summarized by Susan Elisabeth Calico

Download as a PDF.

Recent News

Recent Forum Posts

  • Graves, hyperthyroidism, thyrodectomy, eye problems

    June 13, 2019, 4:39 a.m.

    Thyroidectomy does make it much less likely to get the eye disease, but it does happen. Having had TED and...

  • Orbital Decompression

    June 11, 2019, 5:52 p.m.

    Thank you! I appreciate your help.

  • t3 and t4 in range, TSH low

    June 11, 2019, 3:17 p.m.

    the T4 and T3 may still be within the normal range ?

  • Graves, hyperthyroidism, thyrodectomy, eye problems

    June 11, 2019, 8:46 a.m.

    Hello and welcome - perhaps your fiance is related to Sir Robert Graves, an Irish physician who was one of...

  • Graves, hyperthyroidism, thyrodectomy, eye problems

    June 9, 2019, 6:35 p.m.

    Hi all! I’m so glad I finally found a support forum! So I’m 1 year post surgery of having my thyroid out. My...

  • Orbital Decompression

    June 7, 2019, 3:12 p.m.

    I had my orbital decompressions done by Dr Douglas at Kellogg Eye in Ann Arbor, Michigan. We met his fellow,...

  • Orbital Decompression

    June 7, 2019, 1:16 p.m.

    Kimberly, After going through and understanding all of the billing for my orbital decompression - I don't...

  • Orbital Decompression

    May 28, 2019, 5:45 a.m.

    Hi there - I am in the same boat as you. I have not scheduled as I am also waiting for more information about...

  • Blood Pressure problems and Graves Disease

    May 26, 2019, 8:14 a.m.

    Once my hyperthyroidism was resolved with thyroidectomy, I have had no BP issues. However, long before...

  • Blood Pressure problems and Graves Disease

    May 25, 2019, 4:47 p.m.

    Hi all, It's been awhile since I posted. I had GD with TED. Diagnosed in 2016, eye surgeries in 2017 with...

  • Orbital Decompression

    May 24, 2019, 4:28 p.m.

    Hello and welcome - Pricing is a real challenge for any procedure, as there can be huge swings between the...

  • Orbital Decompression

    May 24, 2019, 4:25 p.m.

    Hello, I am scheduling orbital decompression with Dr. Raymond Douglas. His office states that he does not...

  • Patient Education Event in Seattle on June 30th!

    May 21, 2019, 2:27 p.m.

    Please join us for a special patient education event at the Crowne Plaza Seattle Airport! Hear the latest...

  • Mood Swing

    May 17, 2019, 6:19 p.m.

    Hello - This video from Dr. Ira Lesser will hopefully shed some light behind the *why* of the mood issues....

  • Mood Swing

    May 15, 2019, 7:45 p.m.

    Hi all, I love being around people. I love to smile and being helpful as much as I could. However, often...

Questions? Problems? Please contact us at [email protected] or 877-643-3123.

GDATF on Facebook

Support the GDATF and become a member today!

© 2019 Graves' Disease & Thyroid Foundation