China's guidelines recommend that [5] the replacement and supplementary treatment of levothyroxine sodium tablets (L-T4) is the key measure in the case of thyroid hormone deficiency during pregnancy; the European Thyroid Association (ETA) [6] believes that all pregnant women with SCH during pregnancy should be treated with levothyroxine sodium tablets (L-T4); the American Thyroid Association (ATA) [7] recommends L-T4 treatment for SCH in pregnant women with resistance to thyroid peroxidase antibodies (TPO-Abs) positive. This evidence concerns the gene TPO and spindle cell hemangioma.