Objective: To determine the predictive value and the quality of supernatant sperm (SS) achieved by a simple laboratory technical modification after testicular sperm extraction (TESE).
Design: A retrospective analysis.
Setting: An IVF unit in a university medical center.
Patient(s): Azoospermic patients undergoing TESE between January 2001 and December 2006.
Intervention(s): Before the mechanical shredding, the testicular specimen in toto was placed in medium. The medium was spun and the pellet resuspended and transferred for SS detection. Then a wet preparation of the testicular tissue was shredded roughly and inspected for tissue sperm (TS) as described.
Main outcome measure(s): Detection of SS versus TS, fertilization and pregnancy rates (PR) after intracytoplasmic sperm injection (ICSI) with SS versus TS.
Result(s): The SS was detected in all specimens where TS was eventually found, independent of their testicular pathology. When the supernatant was spermatozoa-negative, no spermatozoa were detected in the tissue. For embryos derived from ICSI the fertilization rate of SS was significantly higher than TS (52% vs. 44%), whereas the PR was comparable.
Conclusion(s): The SS serves as an excellent predictor of TESE outcome and as a superior source for fertilization. This modified technique enables faster decision of TESE outcome and an easier switch to donor sperm when available.