Slight pain in the stomach during pregnancy may be caused by physiological reasons as well as pathological reasons such as pre-miscarriage and ectopic pregnancy. 1. Physiological reasons: with the increase of pregnancy weeks, the enlarged uterus will have some pulling effect on the pelvic floor ligaments, and the slight pain in the stomach, can be relieved after resting appropriately, and is not accompanied by other symptoms, which is a physiological phenomenon and does not require special treatment. 2. Pathologic causes: (1) Pre-eclampsia: it can also cause slight pain in the stomach, accompanied by a small amount of vaginal bleeding, ultrasound examination is clear that the normal intrauterine pregnancy, combined with the clinical manifestations and progesterone, blood HCG (human chorionic gonadotropin) level measurement can assist in the diagnosis, and you need to comply with the doctor’s advice and actively preservation of the fetus treatment. (2) Ectopic pregnancy: mainly manifested as slight pain in one side of the lower abdomen, irregular vaginal bleeding and other symptoms, when the pregnancy site rupture can be tear-like pain, ultrasonography, vaginal fornix puncture and blood HCG and other tests to assist in the diagnosis. (3) Acute gastroenteritis: mostly caused by unclean diet or improper diet, it can be accompanied by diarrhea, nausea, vomiting and slight pain in the lower abdomen, which can be diagnosed by combining with medical history and clinical manifestations. When the pregnancy stomach slight pain can go to the hospital for further examination, in order to identify the cause, and actively deal with.