You can’t tell if a woman’s swollen calves are a precursor to a serious illness by her swollen calves. Swollen calves can be caused by hypothyroidism, varicose veins in the lower extremities, and other diseases such as nephrotic syndrome. 1. Hypothyroidism: Hypothyroidism is mainly caused by autoimmune diseases, drugs and other factors. Patients will have weakness, dull expression, swelling of hands and feet, etc. After active standardized treatment, the prognosis of patients is better. 2. Varicose veins of the lower limbs: Varicose veins of the lower limbs are mainly caused by the abnormal structure of the vein wall and the high pressure of the veins, etc. The main symptoms of the patients are soreness and swelling of the lower limbs, mild oedema, and heavy limbs and weakness, etc. The main symptoms of the patients are soreness and swelling of the lower limbs. 3. Other: nephrotic syndrome, heart failure and other diseases can also lead to female patients with calf swelling, need to actively standardize the treatment, otherwise the prognosis is poor. Female patients with symptoms of unexplained calf swelling, should promptly consult a doctor to identify the cause of the disease, and follow the doctor’s instructions for treatment.