Seven pregnancies and deliveries from non-mosaic Klinefelter syndrome patients using fresh and frozen testicular sperm

Purpose: The aim of this study was to investigate the feasibility of using frozen-thawed testicular sperm as well as the timing of testicular sperm extraction (TESE) in patients with non-mosaic Klinefelter syndrome. Methods: Intracytoplasmic sperm injection (ICSI) was performed in six of 17 (35%) patients whose sperm was recovered by TESE. Multiple biopsies of both testes were performed on the day of oocyte retrieval in all but one of the six patients. Results: Seven pregnancies and deliveries were achieved in five couples, and one couple was unsuccessful. Five pregnancies were achieved using fresh motile sperm, and two were achieved using frozen-thawed sperm. Sperm cryopreservation was not possible in one of the five couples because of the small number of recovered sperm, and possible in four other couples for subsequent ICSI. One woman whose husband had TESE performed prior to ovarian stimulation did not become pregnant. This may be due to the attainment of only a few immotile sperm following the frozen-thawed procedure. Conclusion: The outcome of ICSI using fresh or frozen-thawed testicular sperm in patients with non-mosaic Klinefelter syndrome was identical; however, TESE should be performed on the day of oocyte retrieval until such time as a procedure with a higher sperm yield from TESE is available. Moreover, an improved recovery procedure after cryopreservation-thawing of a single spermatozoon must be developed.