Objective: To compare embryos obtained after IVF and intracytoplasmic sperm injection (ICSI) regarding morphology and the likelihood of achieving clinical pregnancy.
Design: Case-control study.
Setting: An IVF unit controlling 1,310 cycles in 1996.
Patient(s): Women having a total of 477 IVF and 475 ICSI consecutive cycles.
Intervention(s): Ovarian stimulation, IVF-ET, or ICSI-ET for all couples.
Main outcome measure(s): Number of grade-A embryos transferred, preclinical pregnancy losses, and clinical pregnancy rates in IVF and ICSI cycles.
Result(s): In comparison with the ICSI group, the IVF group showed significantly more grade-A embryos available for transfer (mean, 2 +/- 1.6 versus 1.8 +/- 1.5), significantly fewer preclinical pregnancy losses (1.6% versus 4%), and significantly higher clinical pregnancy rates (25% versus 19.1%).
Conclusion(s): Embryos obtained after IVF are superior to those obtained after ICSI in relation to embryo morphology and the likelihood of achieving clinical pregnancy.