Determining the cause of acute pelvic pain in the female patient is often a clinical challenge. Diagnostic imaging can be invaluable in this situation. Ectopic pregnancy, pelvic inflammatory disease, and hemorrhagic ovarian cysts are the most commonly diagnosed gynecologic conditions presenting with acute pelvic pain. Ovarian torsion and degenerating fibroids occur less frequently. Other causes to consider include endometriosis, and postpartum causes such as endometritis, or ovarian vein thrombosis. Finally, nongynecologic conditions may overlap in their presentation of acute pelvic pain and should also be considered. The most important of these is acute appendicitis.