Fertilization failure is a common issue in human IVF programs. A study looked at 294 IVF cycles and found that 13% had fertilization failure. Male factor patients had a higher rate of failure. Patients with poor sperm quality were more likely to experience failure. Patients with fewer mature eggs were also more likely to have fertilization failure. A test using hamster eggs did not predict sperm's ability to fertilize eggs. Patients with severe sperm issues may benefit from micromanipulation in future IVF attempts.