The redness of the anal folds in late pregnancy is mostly considered to be caused by fistula, hemorrhoids, perianal eczema and other diseases. 1. anal fistula: the disease is an infectious disease, pregnant women with bacterial infection in the anal area to form abscesses, mostly accompanied by perianal redness, purulent secretions flow and other symptoms. 2. Hemorrhoids: internal hemorrhoids prolapse after the cause of anal closure is not tight, secretion outflow stimulation of perianal skin, will cause the patient anus moisture discomfort and itching. 3. Perianal eczema: in addition to the symptoms of anal redness and itching, local skin is often accompanied by erythema, blisters, flaking and other skin lesions. It is recommended that if the above symptoms occur for a long time, you should go to the hospital in time, clarify the cause of the disease, and choose the appropriate treatment program under the guidance of the doctor to avoid aggravation of the condition.