The slight pain that may occur in the abdomen during the first week of pregnancy is usually considered to be a normal physiological phenomenon caused by early pregnancy reaction. In addition, it may be related to a variety of pathological factors, such as ectopic pregnancy, pre-eclampsia, etc. If accompanied by other abnormalities, it is necessary to promptly consult a doctor to clarify the cause: I. Physiological factors When you are one week pregnant, as the fertilized egg is bedded and growing in the uterus, it will cause contraction of the uterus, so some women will subjectively feel abdominal pain. In addition, the more abundant blood flow to the uterus after pregnancy causes pelvic congestion which may cause discomfort and lead to abdominal pain. The enlargement of the uterus can cause stretching of the surrounding ligaments, which can also cause jerk-like pain. This condition can usually be relieved by proper rest and distraction, and attention can be paid to regular maternity checkups. When a tubal pregnancy rupture occurs, it will show tearing-like pain, accompanied by irregular vaginal bleeding or coffee-colored discharge; 2. Pre-eclampsia: it often shows paroxysmal lower abdominal pain, accompanied by a small amount of vaginal bleeding, due to uterine contraction causing lower abdominal pain, and the symptoms often persist without relief. Therefore, early pregnancy-related examinations should be improved in time when you are one week pregnant to confirm whether there are any abnormalities in your body. When discomfort occurs and the symptoms cannot be relieved, it is important to seek medical attention in time to clarify the cause for symptomatic treatment to avoid adverse consequences to the pregnant woman and the fetus.