The most important effect of hyperthyroidism on the fetus is that it can cause premature birth, stillbirth, perinatal death and fetal malformation. According to one study, 35% of women with hyperthyroidism in pregnancy had hyperthyroidism for more than 3 months during the neonatal period, 27% of newborns had psychomotor abnormalities, and 42% of fetuses had growth retardation. Therefore, once hyperthyroidism is diagnosed, it should be treated promptly, not only for the sake of the mother, but also for the sake of the potential hyperthyroidism of the fetus (especially if the mother is TSAB positive). If you have to get pregnant, you have to go to the hospital and get rid of your hyperthyroidism before you get pregnant.