A 21-year-old nulliparous woman presents with fever for 3 days and lower abdominal pain for 1 week. She also experienced deep dyspareunia during the preceding several weeks. Her last menstrual period was 2 weeks ago. She has a single regular sexual partner. An intrauterine device was implanted for contraception around 3 months ago. Her medical and surgical histories are unremarkable. A urine pregnancy test is negative.