Graves disease is a condition where the thyroid gland makes too much thyroid hormones. This is called hyperthyroidism or overactive thyroid. Graves disease is the most common cause of hyperthyroidism during pregnancy. Having too much thyroid hormone speeds up the way the body uses energy and controls growth.

A healthy thyroid gland works normally in pregnancy. Fewer than 1 in 100 people has an overactive thyroid in pregnancy. Graves disease is a problem with the body's immune system. Researchers believe it's caused by an antibody that sets off the thyroid gland to make too much hormones.

The disease is most common in young to middle-aged adults. It tends to run in families.

• Goiter (too-large thyroid gland bulging in the front of neck)
• Bulging eyes
• Thickened skin over the shin
• Nervousness
• Irritability
• Sweating more than normal
• Thinning of the skin
• Fine, brittle hair
• Weak muscles, especially in the upper arms and thighs
• Shaky hands
• Fast heartbeat
• High blood pressure
• Increased bowel movements
• Weight loss
• Sleeping problems
• Eye sensitivity to light
• Staring
• Confusion
• Goiter in the developing baby

The symptoms of hyperthyroidism may look like other health conditions. Always see your doctor for a diagnosis.

The doctor will ask about your health history. They'll do a physical exam and ask about symptoms. Graves disease is diagnosed with a blood test to measure the amount of thyroid hormone.

The goal of treatment is to keep the thyroid hormone levels normal. Treatment may include:

• Frequent checks of thyroid levels throughout pregnancy.
• Antithyroid medicines.
• Surgery to remove the overactive part of the thyroid.

Radioactive iodine is used to treat the condition in people who are not pregnant. But this treatment isn't safe in pregnancy.

If you have Graves disease, you can take steps to have a healthy pregnancy. Get early prenatal care and work with your doctor to manage the disease.

Graves disease usually gets worse in the first half of pregnancy. It gets better in the second half, and then gets worse again after delivery.

It's important to keep your thyroid levels normal. Hyperthyroidism that is out of control may lead to preterm birth. This is birth before 37 weeks of pregnancy. It can also lead to low birth weight of the baby. The most common complication is preeclampsia. This is a kind of high blood pressure of pregnancy.

A severe life-threatening form of hyperthyroidism called thyroid storm can happen in some pregnancies. This is a condition in which there are very high levels of thyroid hormone. It can cause high fever, dehydration, diarrhea, fast and irregular heartbeat, shock, and even death, if not treated.

Medicines to treat hyperthyroidism in the past have been associated with a risk of birth defects, however this risk is unclear and very rare. Your doctor will discuss the type of medicine used in pregnancy to treat hyperthyroidism and minimize this risk. Untreated hyperthyriodism greatly increases the risk to you and your baby. A condition called neonatal hyperthyroidism may happen in a few newborns if the hyperthyroidism is not treated. It's usually short term and doesn't cause problems for the baby, but carefully keeping track is important. Untreated hyperthyroidism can lead to thyroid storm that can result in loss of the pregnancy.

• Graves disease is a condition where the thyroid gland makes too much thyroid hormones. It's the most common cause of hyperthyroidism during pregnancy.
• The disease is most common in young to middle-aged adults. It tends to run in families.
• The goal of treatment is to keep the levels of thyroid hormones normal.
• The most common complication is preeclampsia, a kind of high blood pressure of pregnancy.

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your doctor tells you.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you.
• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your doctor if you have questions, especially after office hours or on weekends and holidays.