If there is abdominal pain when you are pregnant, the most likely causes are the following two categories: first, physiological causes, which are a normal physiological phenomenon, with the increasing size of the uterus at the beginning of pregnancy, hormone levels continue to rise, there is a slight swelling and pain in the lower abdomen, which is a normal physiological reaction. The second category, pathological causes, may be habitual miscarriage, pre-eclampsia, this pain will usually be accompanied by vaginal bleeding, must pay attention to, timely medical treatment. It may also be caused by some other diseases, such as gastrointestinal diseases, including acute gastroenteritis and urinary system diseases. Therefore, if you have abdominal pain when you are pregnant, it is recommended to go to a regular specialized hospital to improve the relevant examination and give timely and effective symptomatic treatment after a clear diagnosis.