Comparison of Intracytoplasmic Sperm Injection and Partial Zona Dissection followed by Insemination in Hamster Oocytes

Lee, Yu Il; Kwon, Young Sook; Park, Hyun Jeong

Abstract

OBJECTIVES: This study was to investigate the fertilization rate after intracytoplasmic sperm injection (ICSI) or partial zona dissection (PZD) of human and hamster sperm into hamster oocyte in in vitro fertilization (IVF). In addition, the possibility of clinical application was evaluated by the comparison of usefulness and difference of these method. MATERIALS AND METHODS: Hamster immature oocytes were obtained from oviducts superovulated by PMSG and hCG, and hamster sperms were obtained from epididymis. The freezed human sperms were thawed before use. Fertilization were confirmed by two pronuclei, one pronucleus, swollen sperm head or/and two polar bodies at 7~8 hour after ICSI or PZD. RESULTS: The fertilization rates after ICSI and PZD of human sperm to hamster oocyte were 3.6%, 64.2%, 73.6%, and 55.6% for negative control, positive control, ICSI, and PZD respectively, suggesting that ICSI only showed improved fertilization rate (p<0.01). The fertilization rates after ICSI and PZD of hamster sperm to hamster oocyte were 11.1%, 51.2%, 39.6%, and 72.7% for negative control, positive control, ICSI, and PZD respectively, suggesting that PZD only showed improved fertilization rate (p<0.01). PZD showed significantly higher fertilization rate than ICSI (p<0.05). CONCLUSIONS: As for the fertilization rate by ICSI and PZD using hamster oocyte in IVF, ICSI technique was considered to be more useful for human sperm and PZD technique for hamster sperm. Therefore, ICSI technique was considered more appropriate for experimental application using human sperm and hamster oocyte.