In the fifth month of pregnancy, the feeling of small abdominal swelling and distension, if not particularly obvious, is a normal performance, because in the middle of pregnancy, the fetus grows faster, the uterus will also grow, the uterus in the process of growth, there will be a slight distension or tingling sensation. During pregnancy, the uterus in most cases will be in a right-handed state, will compress the abdominal aorta, resulting in venous reflux obstruction, there will also be a slight swelling and pain, this situation does not need to be overly nervous, usually try to pay attention to rest, do not overwork, you can take the left side of the lying position to rest, is conducive to blood circulation, to reduce the abdominal aortic compression, and conducive to the reflux. Usually should pay attention to observe whether the pain is serious, if the swelling pain is serious, it may lead to preeclampsia, or gynecological inflammatory infection, need to pay attention to distinguish.