Hypothyroidism is a disease of the thyroid gland that occurs in women, and hypothyroidism is no exception. Many female patients suffer from hypothyroidism under the pressure of life and work, but also suffer from hypothyroidism. Hypothyroidism (referred to as hypothyroidism) is a disease caused by a decrease in the synthesis and secretion of thyroid hormones, or their physiological effects are insufficient to reduce the body’s metabolism. According to its etiology, it is divided into three categories: primary hypothyroidism, secondary hypothyroidism and peripheral hypothyroidism. If hypothyroidism is not effectively controlled when a woman is pregnant, it will have a great impact on the fetus. A number of studies have shown that pregnant women with clinical hypothyroidism, subclinical hypothyroidism, low T4emia or TPOAb positive will cause a significant increase in miscarriage and pregnancy complications, and cause fetal brain development disorders, resulting in a 6-8 point drop in IQ of the offspring, and women with the above diseases account for 10% – 15% of pregnant women. 15%. Therefore, women must pay attention to monitoring thyroid function when they are pregnant, especially women with previous hypothyroidism. 2, increase the chance of birth defects in children Pregnant women with hypothyroidism will increase the birth defects in children, the United States study shows that the mother hypothyroidism, the baby’s brain, kidneys, heart and other abnormalities are likely to occur. The proportion of birth defects (brain, kidney, heart defects and cleft lip, cleft palate, multi-finger, etc.) in infants is about 18%, while in the general population, the proportion is only about 3%. The mothers-to-be with hypothyroidism need to pay special attention to the following points: 1. while T4 replacement therapy, should strengthen nutrition, pay attention to the correct iodine supplementation, pay attention to rest, do not overwork. 2. 2. Have regular prenatal checkups, pay attention to the growth of weight, abdominal circumference and uterine height, and monitor fetal growth and development with ultrasound. 3. At the time of delivery, cord blood should be kept and thyroid function and TSH should be tested. In addition to hypothyroid women who need to control their condition before pregnancy, ordinary women are also prone to hypothyroidism after pregnancy. The prevalence of hypothyroidism among pregnant women in China is as high as 10-15%, so we hope that pregnant women must pay attention to monitoring the function of thyroid gland before 8 weeks of pregnancy to ensure the health of both mother and child.