Swelling of the face in late pregnancy is usually divided into two cases, one is a physiological phenomenon, due to the enlargement of the fetus in late pregnancy and compression of the inferior venous blood circulation system, resulting in swelling of the face. The other is a pathological phenomenon, such as hypertension during pregnancy, kidney disease and other organ function abnormalities, resulting in swollen face in late pregnancy. I. Physiological phenomenon: swelling may occur throughout pregnancy, especially in late pregnancy, when the fetus increases and presses on the venous blood circulation system, and poor blood circulation easily causes swelling. Swelling during pregnancy first appears in the lowest parts of the body, such as the ankles, and gradually worsens and spreads upward later, which can involve the face and cause swelling of the face during late pregnancy. Physiological edema can change with body position, with the characteristics of light in the morning and heavy in the evening, after resting flat at night, the degree of edema can generally gradually reduce. 2. Pathological phenomena: 1. Hypertension during pregnancy: hypertension during pregnancy may lead to insufficient heart function, which prevents smooth venous blood return and infiltration of body fluids into the tissue interstitial space, easily forming edema, thus showing puffiness in the face; 2. Kidney disease: decreased kidney function, resulting in decreased glomerular filtration rate, leading to retention of water and sodium in the body, so water infiltration into the tissue interstitial space causes facial edema. Simple edema during pregnancy generally does not require special treatment, but the presence of edema along with other symptoms requires timely medical attention to avoid aggravation of the condition and endangering the life of the mother and fetus.