During the past decade, few fields in medicine have changed as dramatically as reproductive medicine and the treatment of male infertility. Whereas previously only men with obstructive azoospermia were candidates for treatment, either through surgical reconstruction or sperm aspiration, now even men with nonobstructive azoospermia are able to achieve pregnancies without having to resort to donor sperm. The extraordinary success of assisted reproduction after sperm retrieval for azoospermic men is the result of three important discoveries. First is the clinical observation that epididymal transit of sperm is not required for successful fertilization. Second is the recognition that significant heterogeneity in testicular biopsy specimens exists. Lastly is the advent of intracytoplasmic sperm injection (ICSI), which has enabled fertilization regardless of the degree of sperm impairment or retrieval source as long as sperm are viable. These three discoveries have enabled fertilizations and pregnancies for men previously referred for donor insemination or adoption, and have therefore broadened the indications for sperm retrieval. This review is intended to describe in detail the available techniques for the recovery of sperm, with emphasis on the latest technique, testicular microdissection for sperm retrieval in nonobstructive azoospermia.
