The duration of redness in early pregnancy is related to the cause of the redness. Physiological redness in early pregnancy usually lasts 1-3 days, while pathological redness is related to the specific cause. Physiological redness in the first trimester is a physiological reaction to the fertilization of the egg, which usually lasts 1-3 days and the amount of bleeding is small. Pathological redness, on the other hand, tends to be heavy and prolonged, and may be accompanied by abdominal pain and low back pain. If the redness is caused by pre-eclampsia, it may last about 3-5 days after treatment, and if the treatment is not effective, the duration of redness will be further prolonged. If the redness in early pregnancy lasts for more than 3 days or the bleeding volume is large, it is necessary to consider the possibility of pathological causes and go to the obstetrics and gynecology department of the hospital in time to clarify the cause and then treat it accordingly.