Parents-to-be are concerned about what factors can interfere with or limit the conception of a healthy baby. What is clear is that thyroid disorders during pregnancy can adversely affect the health of the mother and child, especially the development of the fetal brain, and therefore, pre-pregnancy screening of thyroid function is mandatory and should be taken seriously and not perfunctorily. The main screening indicators are serum TSH (thyrotropin), FT4 (free thyroxine) and TPOAb (thyroid autoantibodies). As one of the common diseases among women of childbearing age in China, thyroid disorders during pregnancy include clinical hypothyroidism, subclinical hypothyroidism and positive thyroid autoantibodies (TPOAb), etc. The prevalence of these three diseases among women in the first half of pregnancy is 0.6%, 5.27% and 8.6% respectively, which means that 1 in 10 mothers-to-be may be affected by thyroid disorders. This means that 1 in 10 mothers-to-be may be affected by thyroid disease, which overshadows the joy of adding a child to the family. The health of both mother and child is affected Thyroid disease during pregnancy not only has a high incidence and wide impact, but also has adverse effects on the health of mother and child. Several studies in China and abroad have shown that clinical hypothyroidism, subclinical hypothyroidism and TPOAb positivity in pregnant women have different degrees of negative effects on pregnancy outcomes and neurointellectual development of the offspring. Clinical hypothyroidism in pregnancy, for example, increases the risk of adverse pregnancy outcomes such as preterm birth, low birth weight and miscarriage, increasing the risk of miscarriage by 60%, hypertension in pregnancy by 22% and stillbirth. There are also adverse effects on fetal neurointellectual development, such as the potential for lower IQ scores and delayed motor, language and attention development in children. Based on this evidence, treatment should be started as soon as clinical hypothyroidism is identified, and treatment goals should be reached as soon as possible. Despite the seriousness of the risk, the outcome is usually better with timely detection and scientific intervention. In clinical hypothyroidism in pregnancy, for example, there is no evidence of adverse pregnancy outcomes or fetal mental development after effective treatment, and the fetus does not require any additional monitoring measures. Pregnant women with clinical hypothyroidism should have their thyroid function tested every 4 weeks during the first half of pregnancy (1-20 weeks) and at least once during 26-32 weeks of gestation. Preconception screening is optimal Studies and cost-benefit analyses have shown that screening the entire gestational population is preferable to screening the high-risk pregnancy population. The timing of thyroid disease screening should be chosen before 8 weeks of gestation. It is best to screen for thyroid indicators before pregnancy, so that if the disease is diagnosed, the pregnancy can be treated effectively beforehand to ensure maximum maternal and infant health. The main screening indicators are serum TSH, FT4 and TPOAb.