This document provides guidance for evaluating primary amenorrhea. It recommends beginning with a pelvic exam or ultrasound to check for the presence or absence of a uterus. If the uterus is present, serum FSH levels are checked - increased levels point to ovarian failure while decreased levels suggest hypogonadism. If the uterus is absent, karyotyping and cranial MRI are suggested, with various potential diagnoses depending on the karyotype and hormone levels.