If the examination determines that the pregnancy is intrauterine for 56 days, the stomach pain is often caused by the following reasons: 1, with the increase of the uterus, the ligaments of the uterus will be involved in pain, so it will lead to pain in the lower abdomen, often at rest the symptoms of pain will be significantly reduced, this situation is recommended to pay attention to rest, do not overwork, do not need to give special treatment. 2, caused by preterm abortion, in the clinical In the clinical situation, the contraction of the smooth muscle of the uterus due to a drop in progesterone, sexual intercourse or trauma can cause pain in the lower abdomen, and some people also have a small amount of vaginal bleeding. In this case, it is recommended to give active antirefetal treatment and to know whether the fetus is still developing normally at this time.