The stomach pain in the 5th month of pregnancy may be caused by physiological reasons, premature miscarriage, acute gastroenteritis and other reasons. 1. Physiological reasons: with the increase of pregnancy weeks, the uterus will gradually increase in size, the bottom of the uterus has reached the umbilicus 1 horizontal finger in the fifth month of pregnancy, due to the pulling of the surrounding ligaments and the lower abdomen caused by a slight swelling and discomfort, which is a normal physiological phenomenon, and can be relieved after resting appropriately. 2. Pre-eclampsia: It will cause paroxysmal swelling and pain in the stomach, accompanied by vaginal bleeding, ultrasound suggests that the development of the fetus is normal, you need to follow the doctor’s advice to rest, and actively preservation of the fetus and prevention of infection treatment. 3. Acute gastroenteritis: can also cause abdominal distension and discomfort, can also be accompanied by nausea, vomiting, diarrhea and other symptoms, mostly from unclean diet or improper diet history, combined with clinical manifestations and medical history can help diagnosis. When you are 5 months pregnant, you need to go to the hospital to find out the cause of the bloating and pain, and actively deal with it.