Objective: To report an improved sperm recovery procedure from testicular biopsy specimens for intracytoplasmic sperm injection (ICSI).
Design: Case series and controlled study.
Setting: Procedures were performed in a tertiary IVF center.
Patient(s): Nonobstructive azoospermic cases (15 patients) and obstructive azoospermic cases (5 patients).
Intervention(s): Intracytoplasmic sperm injection was carried out using testicular sperm isolated from a testicular biopsy specimen either with or without erythrocyte lysing buffer treatment.
Main outcome measure(s): The time required to collect spermatozoa and the intactness and fertilization and developmental rates of oocytes.
Result(s): In 7 of the 15 nonobstructive cases, it was possible to perform ICSI when, after shredding of the testicular tissue, no (or virtually no) sperm were present. There was no difference in the fertilization rates (83% and 68%) and developmental rates (87% and 89%) of the 54 sibling oocytes from another 5 patients in whom ICSI was carried out with sperm either treated or not treated with erythrocyte lysing buffer.
Conclusion(s): Erythrocyte lysing buffer treatment of testicular biopsy specimens enhances the efficiency of sperm collection in those cycles in which spermatozoa are present and does not affect fertilization and embryo development.