Snapshot A 17-year-old female presents to the pediatrician with a concern of not yet beginning menses. Her friends in high school have already begun menses a few years ago, and this brings the patient great distress. She reports being sexually active and uses condomns consistently. She does not use any other form of contraception. She denies pelvic pain. On physical exam, there is normal breast development; however, her uterus is not palpable. This is confirmed by pelvic ultrasound. Karyotype returns as 46, XX and serum testosterone level is appropriate for a female. (Müllerian agenesis) Introduction Absence of menarche by the age of ≥ 15 years login to view 2 more bullets Etiology most cases are due to genetic causes or anatomical abnormalities login to view 17 more bullets Presentation Symptoms login to view 1 more bullet There are many causes of primary amenorrhea, and depending on the cause, it may affect clinical presentation login to view 2 more bullets Imaging Pelvic ultrasound is needed to determine the presence of a uterus STUDIES In a patient with primary amenorrhea and an increased FSH, the next step in management is karyotyping Differential Pregnancy Contraceptive use Refer to evaluation Treatment Directed at underlying pathology login to view 1 more bullet COMPLICATIONS Infertility