Li Mou and Wang Mou have been married for almost two years and have not had children, because Li Mou was found to have hyperthyroidism soon after the marriage, and has been taking medication since then, the condition is well controlled, and is currently maintained with small doses. The first thing you need to do is to get a good idea of what you are getting into. Can we have this child? If so, what should I pay attention to during pregnancy? On the contrary, the process of pregnancy is an immune tolerance process for the mother to receive sperm, and hyperthyroidism is an autoimmune disease, so it will be reduced. It is generally recommended that patients with hyperthyroidism should wait until their disease is cured and they have completely stopped taking their medication before becoming pregnant. However, if the patient’s disease is well controlled at this stage and only requires low dose medication maintenance, pregnancy is also allowed and is generally considered to have no increased complications during pregnancy and a good prognosis for the mother and newborn. On the contrary, if the hyperthyroidism is poorly controlled, pregnancy is not advisable. Otherwise, miscarriage and preterm delivery will be easily caused. In addition, hyperthyroid pregnant women with hyper-metabolism cannot provide sufficient nutrition and oxygen to the fetus, which may lead to fetal growth restriction and intrauterine distress. In terms of medication, pregnant women with hyperthyroidism should choose propylthiouracil instead of tabazol, as the former has a larger molecular weight when combined with proteins in the pregnant woman’s body and passes through the placenta slowly, so the amount of blood entering the fetus is smaller and will not affect the fetus. In addition, during pregnancy, thyroid function should be closely monitored and the dose of propylthiouracil should be adjusted in time to maintain thyroid function at 1/3 of the upper limit of normal value, and not to overdose, which may lead to hypothyroidism and affect fetal brain development. ATD can be secreted from breast milk and affect fetal thyroid function, so it is not advisable for hyperthyroid patients to breastfeed when taking ATD therapy. However, considering the serious hepatotoxicity of PTU, PTU is no longer used as a first-line drug in the latest ATA guidelines except for the first trimester of pregnancy, and methimazole is preferred for ATD, so methimazole should also be preferred for ATD during breastfeeding!