Pregnant women with subclinical hypothyroidism have no obvious clinical symptoms, while pregnant women with clinical hypothyroidism may have symptoms such as fatigue, chills, facial edema, and loss of appetite. There are individual differences in clinical symptoms. 1. Subclinical hypothyroidism: Pregnant women only have increased levels of thyroid stimulating hormone, but the level of thyroid hormone is still in the normal range, and usually do not have obvious symptoms. 2. Clinical hypothyroidism: pregnant women with elevated thyroid stimulating hormone secretion and lowered thyroid hormone levels are referred to as pregnancy-associated clinical hypothyroidism, in which the patient mostly experiences low metabolic symptoms such as easy fatigue, fear of coldness, and low perspiration, as well as discomfort such as drowsiness, slow reaction time, facial oedema, decreased appetite, and abdominal distension. Pregnant women who experience the above symptoms or suspect hypothyroidism should consult a doctor in time to complete the relevant examinations and follow the doctor’s instructions for appropriate treatment.