This study aimed to determine whether the presence of endometrial polyps discovered during ovarian stimulation affects the outcomes of intracytoplasmic sperm injection (ICSI) cycles. This retrospective descriptive study was conducted in a private assisted reproductive technology unit. Medical records of ICSI cycles performed between January 2003 and December 2004 were reviewed. Patients were divided into three groups: patients with endometrial polyps discovered during ovarian stimulation (group 1, n=15), patients who underwent hysteroscopic polyp resection prior to their ICSI cycle (group 2, n=40) and patients without polyps (group 3, n=956). Main outcome measures were clinical pregnancy rates and implantation rates. Age of the patients, age of the husbands, body mass index, total amount of gonadotrophins used, length of stimulation, peak oestradiol concentrations, peak endometrial thickness and number of embryos replaced were not significantly different between the groups, nor were the pregnancy and implantation rates. Only one patient (12.5%) from the first group experienced miscarriage within 12 weeks of pregnancy. In conclusion, endometrial polyps discovered during ovarian stimulation do not negatively affect pregnancy and implantation outcomes in ICSI cycles.