15-year-old girl presented with primary amenorrhea with orderly appearance of secondary sexual characteristics like breast and pubic hair. What is the next best step for this patient:

In the question the girl is 15 yrs with normal secondary sexual characteristics, she is a case of primary amenorrhea and needs evaluation (reassurance could have been given had the patient been younger than 15 years) The next impoant step would be an USG to check whether she has normal mullerian structures (uterus and tubes) and ovaries or not Hormonal studies and karyotyping are done subsequently to find out the cause.