Primary amenorrhea. Secondary amenorrhea. Pathoshysiology of amenorrhea. Hypothalamus-Pituitary-Ovary-Uterus interaction. Euestrogenic anovulatory amenorrhea. Hypoestrogenic anovulatory amenorrhea. Cryptomenorrhea. Asherman's Syndrome. Gonadal dysgeneis. Turner's Syndrome. Premature Ovarian Failure. Polycystic Ovary Syndrome. Hypogonadrotropic Hypogonadism. Sheehan's Syndrome. Anorexia Nervosa. Late onset congenital adrenal hyperplasia. Cushing's Syndrome. Androgen insensitivity.