PLE-4170

A 25-year-old nullipara went for consultation due to 7 years of irregular menses occurring every 2 to 3 months, with menorrhagia lasting for 8 days. Her BMI is 32 kg/m2 and her BP is 130/90. Physical examination shows darkened skin flexures, particularly in the dorsal neck. Hairs are also noted in the upper lip, chin, and anterior chest. Which of the following is not needed as part of her workup?