PLE-4048

PLE-4048

A 20-year-old woman presents to your office complaining of amenorrhea. She has never had a menstrual period before but complains of mild cyclic abdominal bloating. She reports normal breast development at age 11. She reports that she has become sexually active but finds intercourse painful. Her past medical history is unremarkable. On physical examination, you note normal appearing axillary and pubic hair. Her breast development is normal. A pelvic exam shows a normal appearing external genitalia and a shortened vagina ending in a blind pouch. Which of the following tests would be your first step in diagnosing the patient?