EVIDENCE-BASED ANSWER: The initial evaluation should start with a history, including sexual development, accompanied by a physical examination including assessment of secondary sexual characteristics and genital examination. Initial laboratory studies should include urine pregnancy test, folliclestimulating hormone (FSH), prolactin, and thyroid-stimulating hormone (TSH). The presence or absence of breast development and FSH levels can guide further evaluation (SOR: C, expert consensus based on guideline and case series).