Nonclassical congenital adrenal hyperplasia (NCAH) is a most prevalent hereditary endocrinological disorder that presents with symptoms such as oligomenorrhea. NCAH is difficult to screen due to the recurrent overlap with polycystic ovary syndrome (PCOS). At 120 minutes, checking 17-hydroxyprogesterone (17-OHP) levels and other tests provides a crucial insight into diagnosis and how patients with congenital adrenal hyperplasia (CAH) respond to therapy.