The Prolactin Response to Thyrotropin-Releasing Hormone Differentiates Isolated Gonadotropin Deficiency from Delayed Puberty

It is currently believed that hypogonadotropic hypogonadism (or isolated gonadotropin deficiency) is secondary to lack of delivery of endogenous luteinizing hormone-releasing hormone to the pituitary gonadotrope, whereas delayed puberty is related to retarded activation of the hypothalamic-pituitary axis.1 , 2 The distinction between the two conditions poses one of the most difficult diagnostic problems in endocrinology.2 , 3 When isolated gonadotropin deficiency is associated with anosmia or other congenital anomalies, it is easily differentiated from physiologic delayed puberty.4 However, many patients present without any somatic abnormalities. In such cases, the usual course is to procrastinate. However, prolonged delay in treatment causes severe social embarrassment . . .