Hyperthyroidism has many adverse effects on pregnancy, such as causing miscarriage, placental abruption and thyroid crisis in pregnant women; and on the fetus, such as intrauterine growth retardation, small-for-full-term (SGA) babies, and hyperthyroidism in newborns after birth. Therefore, many women of childbearing age with hyperthyroidism may have the question – can I still get pregnant? How can I minimize the risk if I get pregnant? It is recommended to wait until hyperthyroidism is well controlled before getting pregnant Professor Ma Liangkun from the Department of Gynecology of Peking Union Medical College Hospital told us that it is possible to get pregnant with hyperthyroidism, but it is recommended to wait until it is well controlled before getting pregnant. As we know, the biggest disadvantage of hyperthyroidism medication is that there is a 50% chance of relapse after stopping the medication, which usually occurs within six months to one year after stopping the medication, and the higher the value of thyroid excitatory antibodies (TSAb), the higher the relapse rate. The criteria for good control is that if the thyroid gland is not too large or mildly enlarged, if the thyroid gland has been maintained for more than six months with regular treatment at the lowest dose (tabazol 5mg per day or propecia 50mg per day), and if thyroid function has been maintained in the normal range, and if there is no recurrence of hyperthyroidism for six months to one year after stopping the medication, then pregnancy is possible. If the control of hyperthyroidism is unsatisfactory, surgery or radioactive iodine treatment is recommended. We will strive to maintain normal thyroid function for six months to one year after surgery or radioactive iodine treatment before considering pregnancy. Some patients heard that “radioactive iodine treatment is not good for pregnancy”, but Prof. Ma explained that the radiation effect of radioactive iodine treatment will disappear after six months, and radioactive iodine has no effect on ovarian function. It is safe for the fetus to get pregnant after six months when the radioactive iodine in the body has completely disappeared. However, it is important to be alert to secondary hypothyroidism caused by the treatment. Pregnancy during treatment must follow medical advice If some patients must get pregnant during treatment for some reasons, Prof. Ma recommends that patients must first visit the endocrinology department for consultation and evaluation, and ask the doctor to adjust the medication and dosage. After pregnancy is confirmed, it is also important to follow up with the endocrinology department regularly to adjust the dosage of medication at any time to ensure the health of the mother-to-be and the baby. Of course, obstetric checkups should not be neglected. Doctors need to closely monitor the condition of pregnant women and fetuses in order to diagnose and deal with complications in time. The above content is referenced from the book “263 What to Do About Pregnancy and Thyroid Diseases” edited by Prof. Ma Liangkun, which provides a comprehensive explanation of the changes in thyroid function during pregnancy; how to assess women with thyroid disease before pregnancy; and how to adjust the preparation for pregnancy. Patients with related doubts can find more answers in the book.