Doubt #1: What is hyperthyroidism? Does it affect the baby’s health? Doctor: The thyroid gland is located in the front part of the neck of the human body and is one of the endocrine organs that normally secretes thyroxine for the body’s needs. When the thyroid gland is in a high-functioning state due to various causes, it produces and releases too much thyroxine, resulting in “hyperthyroidism”, or “hyperthyroidism” for short. There are many causes of hyperthyroidism, such as autoimmune-related Graves’ disease, pituitary and thyroid tumors, and excessive iodine intake. 95% of hyperthyroidism in mothers-to-be is Graves’ disease. Hyperthyroidism is characterized by panic, excessive sweating, hyperphagia, fatigue, diarrhea, agitation, anxiety and irritability, etc. Pregnant women’s weight does not increase with the number of months of pregnancy, but rather, they lose weight, and some patients have enlarged thyroid glands in the anterior part of their necks, and protruding eyeballs. Some patients have swollen thyroid glands in the front of the neck and protruding eyeballs. Pregnant women with unexplained symptoms may be suffering from hyperthyroidism. Uncontrolled hyperthyroidism can cause miscarriage, preterm labor, pre-eclampsia, thyroid crisis and placental abruption in the mother-to-be. The fetus may experience intrauterine growth retardation, preterm labor, or even stillbirth. If hyperthyroidism can be controlled, the incidence of risk can be significantly reduced. Doubt 2: How to treat hyperthyroidism in the mother-to-be and is it harmful to the baby? The current treatment of hyperthyroidism includes medication, radioactive iodine treatment and surgery. Drug therapy is the main treatment for hyperthyroidism in pregnancy, and radioactive iodine therapy is not feasible (considering the safety of the fetus). Surgery is generally not advocated, and even if it is done, it should be done with caution. Drug treatment can choose methimazole or propylthiouracil orally. Both drugs have risks, including leukopenia and liver dysfunction in pregnant women, and teratogenicity in the fetus. On balance, propylthiouracil has a relatively low risk when used in the 1st to 3rd trimester, and methimazole is preferred from the 4th trimester onwards. Thyroid function is monitored every 2 to 4 weeks during the initiation of treatment and every 4 to 6 weeks after stabilization, along with blood leukocytes and liver function. During the middle and late stages of pregnancy, the mother’s immune system “compromises” to protect the fetus, and the hyperthyroidism gradually resolves. At this point, the dosage needs to be adjusted downward, and in the second trimester, 20% to 30% of patients may discontinue the medication. Therefore, the mother-to-be must follow the doctor’s instructions for regular follow-up, so as to avoid hyperthyroidism ate into hypothyroidism, the development of the fetus is equally unfavorable. It is recommended that women who have been diagnosed with hyperthyroidism prior to pregnancy should conceive after the hyperthyroidism is cured and the oral medication is discontinued, or six months after undergoing surgery or radioactive iodine treatment. For those who are on medication, if pregnancy is required, it should be carried out after the thyroid function is controlled in an ideal range. Doubt 3: What else should a hyperthyroid mom-to-be pay attention to in her daily life? Hyperthyroidism is easy to lead to the patient’s temperament, and is a consuming disease, mothers-to-be should relax during the illness, keep a calm mind, strengthen nutrition, low salt, low fat, high vitamin, high calorie, high protein, easy to digest diet, such as eggs, milk, lean pork, as well as a variety of fruits and vegetables. In addition, the element iodine is the raw material for the body to synthesize thyroxine. Non-pregnant hyperthyroidism patients are usually required to prohibit iodine diet (such as banning iodized salt and seafood) to inhibit the excessive secretion of thyroxine. However, in the first 6 weeks of pregnancy, the fetus’s thyroid gland is not developed, can not synthesize thyroxine, must rely on the mother to supply thyroxine to promote growth and development. At this time, pregnant women who prohibit iodine plus medication, easy to cause hypothyroidism, so the first 6 weeks of pregnancy to low iodine diet is appropriate, you can eat common iodized salt (iodine 25 mg per kilogram), to avoid the intake of seafood; after 6 weeks of gestation, the fetus relies on maternal iodine synthesis of thyroxine, can be in the guidance of the doctor to the appropriate intake of seaweed, seafood and other seafood. Doubt 4: Some mothers-to-be have hyperthyroidism, why do they not need treatment can also be cured? Doctor: This “hyperthyroidism” is not hyperthyroidism! This kind of “hyperthyroidism” is known as “hyperthyroidism in pregnancy syndrome”, which generally occurs in the first half of pregnancy, and the pregnant woman’s body of the human chorionic gonadotropin production increased, excessive stimulation of thyroxine production related. It is characterized by the onset of hypermetabolic symptoms such as palpitations, anxiety and excessive sweating at 8 to 10 weeks of pregnancy, and thyroid function tests suggesting hyperfunction. Its occurrence is also associated with severe vomiting of pregnancy. Patients with hyperthyroidism syndrome of pregnancy do not need to be treated for hyperthyroidism; symptomatic treatment is sufficient. Thyroid function can return to normal by itself at 14 to 18 weeks of pregnancy. Doubt 5: Can I breastfeed if I take medication for hyperthyroidism? The breast milk excretion rate of propylthiouracil is lower than that of methimazole, and the former will be preferred during breastfeeding with no obvious effect on the baby. However, it is recommended that pregnant women take the drug after breastfeeding is completed, with an interval of 3~4 hours before the next breastfeeding, in order to reduce the concentration of the drug in the milk. The baby’s thyroid function should also be monitored regularly.