Innovations for severe male infertility.

Men affected by substantial defects in spermatogenesis have previously been considered untreatable in nearly all cases. The advances of intracytoplasmic sperm injection and microdissection testicular sperm extraction brought the potential of treatment to a substantial proportion of men with severe infertility. Novel approaches for the restoration of stem cells within the testis that have severely impaired function, and enhancement of spermatogenesis are now being actively investigated. In this issue of Fertility & Sterility, we have three Views and Reviews on these topics, as well as the special topic of fertility preservation for the prepubertal male.