Successful delivery derived from cryopreserved rare human spermatozoa with novel cryopiece

Herein, we report the clinical outcomes following intracytoplasmic sperm injection (ICSI) with cryopiece cryopreserved rare human spermatozoa from severe male factor infertility patients. We established a novel cryopiece system on the basis of previous studies. In this study, 126 spermatozoa from four patients with non-obstructiveazoospermia (NOA) or severe oligozoospermia were stored in cryopiece and then thawed on the day of the oocyte retrieval, 88 (83%) spermatozoa were recovered with a 47.5% (38 of 80) motile rate. Routine ICSI were performed in enrolled 30 MII oocytes from their spouse with their own spermatozoa, respectively. Twenty-two (73%) fertilization and 19 (86%) zygote cleavage were observed. Finally, a total of 11 embryos were achieved and each female patient received a transplantation of two fresh embryos. Four healthy babies were born at term. In conclusion, our novel cryopiece can be applied in assisted reproduction through ICSI with an effective motile spermatozoa recovery rate, high fertilization rate, and successful pregnancy result.