Comparison of pronuclear stage embryo transfer and in vitro fertilization-embryo transfer following intracytoplasmic sperm injection.

ABSTRACT

To determine whether the mode of embryo transfer (PROST vs IVF) affected the outcome in intracytoplasmic sperm injection (ICSI) cycles, 237 ICSI cycles (106 PROST and 131 IVF) were analyzed. Several parameters, including patient age, duration of infertility, amounts of hMG used, number of mature eggs retrieved and injected, fertilization rate, number of embryos transferred, and clinical pregnancy rate, were compared. Most of the variable factors were not significantly different, except the mean numbers of transferred embryos which were significantly higher in the PROST group. The clinical pregnancy rate showed no statistical difference between PROST and IVF cycles (25.5 and 16.8%; p = 0.139). This study suggests that even the pregnancy rate in PROST cycles was slightly higher than IVF cycles, but there was no statistically significant difference between the two groups.