Current landscape of fertility induction in males with congenital hypogonadotropic hypogonadism.

Congenital hypogonadotropic hypogonadism (CHH) is a rare reproductive disorder caused by deficient secretion or action of gonadotropin-releasing hormone (GnRH) and is a hormonally treatable form of male infertility. Both pulsatile GnRH treatment and combined gonadotropin therapy effectively induce spermatogenesis in 75%-80% of males with CHH, albeit the ejaculate does not usually approach normal semen parameters by WHO criteria. This is in some contrast to the cumulative fertility outcomes in females with CHH on gonadotropin treatment that are indistinguishable from those of reproductively normal females. Emerging data provide insights into early life determinants of male fertility (i.e., minipuberty), and research has identified key predictors of outcomes for fertility-inducing treatment in men with CHH. Such developments provide mounting evidence for tailoring approaches to maximize fertility potential in CHH, although there is no clear consensus to date on the optimal approach to fertility-inducing treatment. This review provides an up-to-date review on the current evidence underpinning therapeutic approaches for inducing spermatogenesis in males with CHH. In the absence of evidence-based clinical guidelines, this synthesis of current evidence provides guidance for clinicians working with males with CHH seeking fertility.