Standard operating procedures (SOPs) for processing both epididymal and testicular spermatozoa are provided.

Since its inception, ICSI has become the most widely used ART technique, and the ultimate treatment for severe male factor infertility. In this chapter, we provide fertilization and clinical pregnancy outcomes with ICSI utilizing oligo-, crypto- and astheno- zoospermic samples. We also describe the negative impact of ooplasmic dysmaturity on fertilization and propose methods to correct it. We also report the selection of spermatozoa with higher genomic integrity using a microfluidic chip in couples with high chromatin fragmentation and complete embryo aneuploidy. This will be followed by a discussion on the safety of ICSI in which we enlist various follow-up studies on the development and health of ICSI offspring through adulthood. To provide an overview on the widespread utilization of this procedure, we comment on the ICSI results reported worldwide.

Since the establishment of in vitro fertilization, it became quickly apparent that approximately half of the couples treated presented with a dysfunctional male gamete. To alleviate this issue, intracytoplasmic sperm injection (ICSI) was introduced to treat men with compromised semen parameters or azoospermia, and more recently high sperm chromatin fragmentation or sperm-linked oocyte activation deficiency. Because of its success, ICSI has been extended for cases with low egg yield, oocyte cryopreservation, and often for preimplantation genetic testing. Due to its versatility and reliability, ICSI has become the most popular ART and will be invaluable for emerging technologies such as in vitro gametogenesis and heritable genome editing. In this chapter, we discuss the development of ICSI, its current applications, and ongoing research that will contribute to the future of reproductive medicine.

The development of surgical sperm retrieval procedures can be considered as the single most important breakthrough in the field of male infertility. Various testicular sperm retrieval procedures exist and are indicated in patients with obstructive and nonobstructive azoospermia, as well as patients with high levels of sperm DNA fragmentation and severe derangements in semen parameters. Microsurgical testicular sperm extraction can be considered the gold standard retrieval method as it allows meticulous and selective sampling of sperm-containing seminiferous tubules, yielding the highest retrieval rate in comparison to other surgical sperm retrieval methods.

Early attempts at surgical sperm retrieval focused on creating artificial spermatoceles in men with vas aplasia or uncorrectable obstructive azoospermia. The collected sperm was used for intrauterine insemination, and success was rare. The major impetus to sperm retrieval came soon after the development of intracytoplasmic sperm injection, which enabled high fertilization rates and live-birth rates using sperm from the testis or epididymis. Initial cases involved men with obstructive azoospermia and sperm were retrieved microsurgically from the epididymis. Subsequently, testicular sperm, obtained by conventional biopsy, were used when sperm could not be aspirated from the epididymis. Retrieval was simplified with the development of percutaneous techniques for extracting epididymal or testicular sperm. Techniques became more complex and varied when it was realized that men with nonobstructive azoospermia may also have sperm in their testes, but these sperm-containing tubules could be very localized. Hence, a variety of percutaneous and open methods were developed that could sample the testes extensively. Initially the sampling was blind, through multidirectional aspiration or multiple random biopsies. However, these blind techniques could still miss localized areas of sperm production. Also, multiple biopsies were shown to cause testicular damage. Hence, microdissection testicular sperm extraction (mTESE) was developed, which involved visual inspection of the entire testicular parenchyma under high magnification. mTESE gives the highest sperm retrieval rates, especially when the testes are small or atrophic.