Management strategies for ICSI cases with extremely poor sperm parameters.

PURPOSE OF REVIEW: Intracytoplasmic sperm injection (ICSI) transformed the treatment of severe male factor infertility by reducing the sperm-cell-to-oocyte ratio to one-to-one. This review summarizes current approaches to identify and utilize rare spermatozoa in men with cryptozoospermia, virtual azoospermia, and nonobstructive azoospermia (NOA): assistive technologies for extended sperm search, approaches to rescue dysfunctional spermatozoa, and novel biomarkers to predict residual spermatogenesis.

RECENT FINDINGS: Extended sperm search protocols involving high-speed centrifugation, high-magnification microscopy, and viability assessments improve sperm recovery in men with cryptozoospermia, virtual azoospermia, and NOA. Microsurgical testicular sperm extraction (microTESE) remains the optimal surgical method for sperm retrieval in NOA men. Sperm treatments, including phosphodiesterase inhibitors to enhance sperm motility and assisted oocyte activation, improve viable sperm identification and fertilization competence, respectively. artificial intelligence-driven imaging can identify extremely rare spermatozoa, while genomic, transcriptomic, and proteomic biomarkers noninvasively predict residual spermatogenesis in NOA patients.

SUMMARY: ICSI has enabled the identification of a single spermatozoon, allowing men with compromised spermatogenesis to father offspring. Beyond sperm identification, rescuing fertilization competence of compromised sperm is crucial. Integrating molecular diagnostics may improve prognostic accuracy and clinical counseling, while emerging technologies like neogametogenesis may offer reproductive options for men with spermatogenic arrest or germ cell aplasia.