In this study, to avoid the virus contamination in the maturation medium by addition of donor follicular fluid (FF) from other in vitro fertilization (IVF) cycles, we examined the outcome of in vitro maturation (IVM) protocol using medium containing patient's own serum. Data were retrospectively collected from 68 irregularly cycling women (31 ± 3.6 years) who were diagnosed as having polycystic ovarian syndrome. Immature oocytes were retrieved transvaginally 36 h after an injection of 10,000 IU hCG. Immature oocytes were matured for 24–26 h in medium supplemented with 10% (v/v) heat-inactivated patient's own serum (group S) or with 20% (v/v) heat-inactivated FF from donors who had undergone IVF cycles (group FF). All mature oocytes were inseminated by intracytoplasmic sperm injection. There were no statistical differences in the rates of maturation (49.2% vs. 45.6%), fertilization (85.0% vs. 84.2%), and pregnancy (16.0% vs. 15.4%) between group S and group FF. The supplementation of patient's own serum to the maturation medium as a substitute for follicular fluid collected from other patients did not affect the outcome of fertility treatment. Thus, we are able to eliminate the risk of transferring infectious diseases by using the patient's own serum.