The thyroid gland and child birth generally have a certain relationship, including the relationship with both the mother and the fetus. 1. Mothers: Pregnancy has a significant effect on the anatomy and physiological function of the thyroid gland. During pregnancy, the thyroid gland is subjected to the effects of thyroid stimulating hormone, thyroid stimulating hormone releasing hormone, and human chorionic gonadotropin, which leads to glandular hyperplasia, an increase in secretion of glandular cells, and an increase in the synthesis and secretion of thyroxine. In addition, in early pregnancy, the thyroxine binding protein produced by the maternal liver increases, and the bound form of thyroid hormone will be elevated, while the free form generally has no significant change; the renal iodine clearance rate will also increase during pregnancy, and the thyroid gland will take up more iodine to ensure that iodine metabolism is balanced during pregnancy. 2. Fetus: thyrotropin-releasing hormone and thyrotropin can be measured in the thalamus and pituitary gland at 10 weeks’ gestation; at 12 weeks’ gestation, thyrotropin as well as thyroid hormone can be detected in the blood of the fetus; thyrotropin rises in newborns at 30 minutes after delivery; thyroid hormone reaches the peak at 24 hours postpartum. Therefore, the form and function of the thyroid gland are affected throughout the process of giving birth to a child. Therefore, there is a relationship between the thyroid gland and giving birth to a child, and it is recommended to consult an endocrinologist or obstetrician/gynecologist.