The vague pain in the abdomen that occurs in the fifth week of pregnancy (early pregnancy), which most women have, is a normal physiological pain. This pain is due to the gradual enlargement of the uterus and the gradual development of the fetus, which causes the uterus to become larger, resulting in a tightening of the uterus and the pulling of the uterine wall, causing pain. The enlarged uterus can also cause pulling and squeezing pain in the ligaments and organs around the uterus. There are also pseudo contractions (a physiological reaction) in early pregnancy that can cause vague pain in the abdomen. However, if the pain is severe and there is vaginal bleeding and redness, it may be pathological. It is important to go to the hospital in time for the appropriate examination, such as the possibility of pre-eclampsia, placental abruption, and other gynecological diseases, such as pelvic inflammatory disease, ovarian cysts, etc. may be present at the same time.