Objective:To demonstrate the clinical outcomes of patients with non-mosaic Klinefelter's syndrome (KS) who underwent preimplantation genetic testing (PGT) with frozen-thawed testicular spermatozoa.Methods:A retrospective case series was performed in the Center for Reproductive Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine from January, 2018 to December 2020. A total of 22 couples were included and 26 oocyte retrieval cycles were completed. Micro-dissection testicular sperm extraction (micro-TESE) was performed for sperm retrieval. Next-generation sequencing (NGS) was conducted for embryo analysis.Results:Euploidy was detected in 33 of 55 (60.0%) embryos. Meanwhile, the numbers of aneuploid and mosaic embryos detected were 10 (18.2%) and 12 (21.8%), respectively, regardless of the lack of sex chromosome abnormality. Finally, 14 couples with euploid embryos completed frozen-thawed embryo transfer (FET). Totally eleven couples had clinical pregnancies, and 6 of them already delivered 5 healthy babies with 1 monozygotic twin.Conclusion:For KS patients, when sperm can be obtained by micro-TESE, the cryopreservation strategy makes the ovarian stimulation procedure more favorable for female partners. The paternal genetic risk of sex chromosome abnormality to their offspring is extremely low in men with KS. Besides intracytoplasmic sperm injection (ICSI) combined with PGT, ICSI procedure is comparable effective but more economical for non-mosaic KS couples. ICSI should be offered as an option for such couples, but monitoring by prenatal genetic diagnosis is recommended.

Objective:To demonstrate the clinical outcomes of patients with non-mosaic Klinefelter's syndrome (KS) who underwent preimplantation genetic testing (PGT) with frozen-thawed testicular spermatozoa.Methods:A retrospective case series was performed in the Center for Reproductive Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine from January, 2018 to December 2020. A total of 22 couples were included and 26 oocyte retrieval cycles were completed. Micro-dissection testicular sperm extraction (micro-TESE) was performed for sperm retrieval. Next-generation sequencing (NGS) was conducted for embryo analysis.Results:Euploidy was detected in 33 of 55 (60.0%) embryos. Meanwhile, the numbers of aneuploid and mosaic embryos detected were 10 (18.2%) and 12 (21.8%), respectively, regardless of the lack of sex chromosome abnormality. Finally, 14 couples with euploid embryos completed frozen-thawed embryo transfer (FET). Totally eleven couples had clinical pregnancies, and 6 of them already delivered 5 healthy babies with 1 monozygotic twin.Conclusion:For KS patients, when sperm can be obtained by micro-TESE, the cryopreservation strategy makes the ovarian stimulation procedure more favorable for female partners. The paternal genetic risk of sex chromosome abnormality to their offspring is extremely low in men with KS. Besides intracytoplasmic sperm injection (ICSI) combined with PGT, ICSI procedure is comparable effective but more economical for non-mosaic KS couples. ICSI should be offered as an option for such couples, but monitoring by prenatal genetic diagnosis is recommended.