This study was undertaken to determine if cisplatin can induce aneuploidy in murine oocytes treated prior to ovulation. Control animals were injected with intraperitoneal (ip) saline and the treatment animals were divided into three different dose schedules for ip cisplatin. After ovulation induction, the oocytes were processed for cytogenetic analysis and the chromosomes were counted. There were significantly less oocytes ovulated in the treatment groups when compared to control animals. There was a significant increase in hypohaploid cells counted in the 7.5 mg/kg treatment group, but the percentages of hyperhaploid and polyploid cells were not increased in the treatment groups. The cytogenetic effects of cisplatin in vivo and in vitro are reviewed.