What are the causes of abdominal pain in early pregnancy?

The symptoms of small abdominal pain in early pregnancy are likely to be caused by threatened abortion, often accompanied by vaginal bleeding. Pregnant women had better go to the hospital to do progesterone, B ultrasound and other examinations, if necessary, need to use progesterone for fetal protection. In addition, it may also be pelvic inflammatory disease, cervicitis and other diseases.