The pain of ectopic pregnancy is roughly similar to menstrual cramps, so in the case of abdominal pain, you cannot tell whether it is ectopic pregnancy or menstrual cramps by the pain. In this case, a blood test for HCG and a pelvic ultrasound are needed to help diagnose the condition. If the HCG value is negative, pregnancy is ruled out and ectopic pregnancy is considered to be dysmenorrhea. If the HCG value is positive, dysmenorrhea is ruled out, but it is a pregnancy-related problem, such as a pelvic ultrasound that reveals a mass outside the uterus, in which case the chances of ectopic pregnancy are very high. If the pelvic ultrasound indicates fluid in the abdominal cavity, a posterior vaginal fornix aspiration is required. If non-clotting blood is drawn, this situation indicates that the ectopic pregnancy has ruptured and emergency surgery is required to remove the ectopic part of the pregnancy and cure it.