Over 2 decades ago, ICSI (intracytoplasmic sperm injection) revolutionized the treatment of male infertility. The ICSI procedure involves injection of a single sperm into each egg at the time of IVF (in vitro fertlization). Before the development of ICSI, couples with sperm issues, what we call "male factor," had very low fertilization and pregnancy rates, even when undergoing IVF. Now a days, because of the use of ICSI, poor sperm quality is a very unusual reason for an IVF cycle to be unsuccessful or to blame for poor fertilization. Over concerns about potentially poor fertilization, many fertility centers have chosen to use ICSI routinely to ensure optimal fertilization even when the male partner's sperm is perfectly normal. At Princeton IVF, our philosophy has always been to allow fertilization to happen "naturally" in the dish when there is no history of sperm issues or poor fertilization. While ICSI had been shown to be quite safe, we feel that a more natural selection process makes more sense and research in the past has suggested that ICSI is only beneficial in male factor patients. A recent large-scale study recently published in the Journal of the American Medical Association has borne this out. ICSI when used in IVF cycles used in couples without sperm issues had lower fertilization and lower implantation rates than non ICSI cycles.