An ectopic pregnancy occurs when a fertilized egg grows outside of the uterus.

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An ectopic pregnancy occurs when a fertilized egg grows outside of the uterus. Almost all ectopic pregnancies—more than 90%—occur in a fallopian tube. As the pregnancy grows, it can cause the tube to burst (rupture). A rupture can cause major internal bleeding. This can be a life-threatening emergency that needs immediate surgery. A history of missed menstrual period, tender breasts, upset stomach along with abnormal vaginal bleeding, low back pain, mild pain in the abdomen or pelvis and mild cramping on one side of the pelvis should guide me to a diagnosis of ectopic pregnancy. I will order a Beta HCG and a pelvic ultrasound to confirm a diagnosis of ectopic pregnancy. My differentials include ectopic pregnancy, appendicitis, bowel obstruction, endometriosis, PID, ruptured ovarian cyst, ovarian torsion, cystitis, pyelonephritis. I would send that patient to the emergency room to see a gynecologist who will remove this ectopic pregnancy via surgery.

Reference

Kruszka, P. S., & Kruszka, S. J. (2010). Evaluation of acute pelvic pain in women. American Family Physician, 82(2), 141–147.