Pregnant women are always thirsty mainly caused by accelerated circulation during pregnancy and gestational diabetes and other reasons. 1. Accelerated circulation during pregnancy: the metabolic rate and body temperature of pregnant women are higher than that of ordinary people, the body water is easily consumed and evaporated, as well as the increase in blood volume after pregnancy, the amount of amniotic fluid needed by the fetus is also increasing, so if the pregnant woman does not consume enough water, the symptom of constant thirst will occur. 2. Gestational diabetes: If pregnant women combined with gestational diabetes, the body of blood sugar increases, there will also be symptoms of thirst, then pregnant women must go to the hospital to do glucose testing, such as diagnosis of gestational diabetes, the need to take medication to control blood glucose, and terminate the pregnancy in due course. It is recommended that pregnant women take enough water every day, eat more fresh fruits and vegetables, and do screening for gestational diabetes between 24 and 28 weeks of pregnancy, and follow up with a doctor if they feel unwell during pregnancy.