A 29-year-old woman presents to the emergency department wit…
A 29-year-old woman presents to the emergency department with sudden-onset severe left lower abdominal pain and light vaginal spotting. She states her last menstrual period was 7 weeks ago and reports a positive home pregnancy test 1 week ago. She also complains of dizziness and left shoulder pain. On examination, she has diffuse lower abdominal tenderness with guarding and cervical motion tenderness. Vital signs are: BP 92/58 mmHg, HR 118 beats/min, respiratory rate 22 breaths/min, temperature 98.7°F (37.1°C), and oxygen saturation 99% on room air. Laboratory results reveal: β-hCG: 2,850 mIU/mL Hemoglobin: 10.2 g/dL WBC: 11.4 × 10³/μL Platelets: 280 × 10³/μL Transvaginal ultrasound demonstrates no intrauterine pregnancy and a 2.5-cm left adnexal mass with a moderate amount of free pelvic fluid. Which of the following is the most likely diagnosis?