Endocrine Abstracts

Congenital hypogonadotropic hypogonadism (CHH) is an inherited disorder characterized by absent, incomplete, or arrested pubertal development during adolescence. The condition results from deficient secretion of gonadotropin-releasing hormone (GnRH) from the hypothalamus with impaired secretion of gonadotropins—luteinizing hormone (LH) and follicle-stimulating hormone (FSH)—from the anterior pituitary gland, leading to insufficient endogenous sex steroid production by the gonads. CHH may occur as an isolated (idiopathic) condition or in association with anosmia, known as Kallmann syndrome. It may also present as part of a broader syndromic disorder or in conjunction with additional pituitary hormone deficiencies. Puberty induction in adolescent or young adult males with CHH has traditionally involved the administration of low, gradually increasing doses of testosterone beginning from 12 years of age. While this approach effectively induces virilization, it does not stimulate testicular growth or support the potential for spermatogenesis. This limitation is particularly relevant in individuals with a history of cryptorchidism or prepubertal testicular volumes (<4 mL). In such cases, pretreatment with FSH may be beneficial to promote expansion of the Sertoli cell population and optimize future fertility potential. Current research advances include a UK-wide prospective randomised controlled trial (the PinG Study) comparing gonadotropin regimens and an international registry (I-HH) to enable lifelong follow-up to determine the impact of these interventions on fertility, physical and psychosocial well-being and quality of life.