If a pregnant woman experiences significant stomach pain during pregnancy, it is usually considered to be caused by uterine contractions and is considered to be a preterm miscarriage or preterm labor. The condition of the pregnant woman changes throughout the course of pregnancy and needs to be monitored dynamically. In the case of abnormal stomach pain, it is important to go to the hospital in time for examination, otherwise it may easily lead to inevitable miscarriage or preterm delivery. If the month is large, it is recommended to do ultrasound to measure the length of the cervix, if the length of the cervix is short, there is a risk of miscarriage or preterm delivery. Vaginal examination can also be done. If the condition of the cervix is already more mature, the probability of miscarriage will increase, and this state is usually necessary to keep the baby.