Short co-incubation of gametes combined with early rescue ICSI: an optimal strategy for complete fertilization failure after IVF.

Failed fertilization after conventional IVF is one of the most frustrating experiences in assisted reproductive technology. "Late" rescue ICSI may be not an optimal strategy for treating unfertilized oocytes. Short co-incubation of gametes combined with early rescue ICSI has some advantages for complete fertilization failure after IVF. We evaluate the strategy and the optimal time for early rescue ICSI. A total of 180 patients underwent short co-incubation of gametes combined with early rescue ICSI treatment for complete fertilization failure after IVF (study group). A total of 494 ICSI patients with male factor infertility served as a control group. Clinical pregnancy rate, implantation rate, and live birth rate in the two groups were compared. The study group was divided into three different rescue time intervals (＜6 h, 6-8 h, and ＞8 h). Clinical pregnancy rate, implantation rate, and live birth rate were comparable between the study group and the control group. There was a negative correlation between clinical outcomes and rescue time interval.