OBJECTIVE: To describe the methods of collection and laboratory preparation of epididymal and testicular sperm; to compare the fertilization and pregnancy rates; and to establish prognostic factors. DESIGN: Retrospective analysis. SETTING: Academic reproductive medicine clinic. PATIENT(S): One hundred twelve consecutive microinjection cycles in 80 patients using either epididymal or testicular sperm. INTERVENTION(S): Sperm were collected by microepididymal sperm aspiration, open testicular biopsy, or fine needle tissue aspiration testicular biopsy. MAIN OUTCOME MEASURE(S): Fertilization rate, implantation, and clinical pregnancy rates. RESULT(S): The fertilization rate was higher with epididymal sperm (67%) than with testicular sperm (50%). Implantation rates (fetal hearts per embryo, testicular: 11%, epididymal: 8%) and pregnancy rates (clinical pregnancy per oocyte collection procedure, testicular: 25%, epididymal: 29%) were not significantly different with epididymal and testicular sperm. Multiple regression analysis showed that normal fertilization rates were significantly lower with testicular sperm, immotile sperm, and severe spermatogenic disorders. CONCLUSION(S): Although fertilization rates are significantly lower with testicular sperm, higher implantation rates resulted in equivalent pregnancy rates. Thus, testicular aspiration of sperm for intracytoplasmic sperm injection is a simple, inexpensive method of sperm retrieval in cases of azoospermia resulting from genital tract obstruction or severe spermatogenic disorder.
OBJECTIVE: To describe the methods of collection and laboratory preparation of epididymal and testicular sperm; to compare the fertilization and pregnancy rates; and to establish prognostic factors. DESIGN: Retrospective analysis. SETTING: Academic reproductive medicine clinic. PATIENT(S): One hundred twelve consecutive microinjection cycles in 80 patients using either epididymal or testicular sperm. INTERVENTION(S): Sperm were collected by microepididymal sperm aspiration, open testicular biopsy, or fine needle tissue aspiration testicular biopsy. MAIN OUTCOME MEASURE(S): Fertilization rate, implantation, and clinical pregnancy rates. RESULT(S): The fertilization rate was higher with epididymal sperm (67%) than with testicular sperm (50%). Implantation rates (fetal hearts per embryo, testicular: 11%, epididymal: 8%) and pregnancy rates (clinical pregnancy per oocyte collection procedure, testicular: 25%, epididymal: 29%) were not significantly different with epididymal and testicular sperm. Multiple regression analysis showed that normal fertilization rates were significantly lower with testicular sperm, immotile sperm, and severe spermatogenic disorders. CONCLUSION(S): Although fertilization rates are significantly lower with testicular sperm, higher implantation rates resulted in equivalent pregnancy rates. Thus, testicular aspiration of sperm for intracytoplasmic sperm injection is a simple, inexpensive method of sperm retrieval in cases of azoospermia resulting from genital tract obstruction or severe spermatogenic disorder.