Abstract: Objective To evaluate the impact of spermatozoa from different sources on normal fertilization of oocytes, embryo
quality and embryo developmental potential in intracytoplasmic sperm injection (ICSI) cycles. Methods A retrospective
analysis was conducted among 197 patients undergoing ICSI cycles in our center. The patients were classified into 3 groups
according to the sources of semen, namely ejaculated spermatozoa group (n=102), percutaneous epididymal sperm aspiration
(PESA) group (n=68), and testicular sperm aspiration (TESA) group (n=27). The ejaculated spermatozoa group was further
classified into oligoasthenoteratozoospermia (n=67) and cryptozoospermia (n=35) subgroups. The normal fertilization,
high-quality embryo, implantation and clinical pregnancy rates were compared among the groups; the rate of high-quality
blastocyst formation in in-vitro culture of non-top quality embryos was also observed. Results The patients with PESA showed
significantly higher normal fertilization rate (75.6%) than those in oligoasthenoteratozoospermia (64.8%), cryptozoospermia
(62.1%), and TESA (61.6%) groups (P<0.05). No significant differences were found in the high-quality embryo, implantation,
and clinical pregnancy rates among the groups (P>0.05). The rate of high-quality blastocyst formation in the in-vitro culture of
non-top quality embryos was also comparable among the groups (P>0.05). Conclusion Although spermatozoa obtained with
by PESA is associated with a higher normal fertilization rate, the sources of spermatozoa do not significantly affect the
embryonic quality and developmental potential in ICSI cycles.