Objective: Cytomegalovirus (CMV) may be transmitted through sperm donation and the use of sperm from men with previous CMV infection has been proscribed by The American Society of Reproductive Medicine for women without prior CMV exposure. The risk of CMV transmission from donated oocytes is unknown. This study sought to define this risk.Design: Prospective study of couples undergoing in vitro fertilization (IVF) in a university setting.Materials and Methods: Forty-nine couples underwent 54 cycles of IVF. Serum from both partners (men: n= 40, women: n= 42) was obtained for detection of IgG antibodies to CMV. Semen prior to preparation (n= 43), semen following preparation (swim-up or Percoll gradient) (n = 26), cervical mucus aspirated at the time of oocyte aspiration (n= 54), and uninseminated oocytes, unfertilized oocytes, and embryos not suited for cryopreservation were frozen in liquid nitrogen. Polymerase chain reaction (PCR) was used for CMV (immediately early gene) detection in all samples collected. CMV-infected and uninfected fibroblasts served as positive and negative controls respectively.Results: Serum CMV antibodies were found in 52% of the women and 38% of the men tested. CMV was detected by PCR amplification in 19% of prepreparation and 4% of postpreparation semen samples, and in 11% of cervical mucous samples. There was no amplification of CMV DNA from oocytes or embryos.Conclusions: As we were unable to amplify CMV DNA from any of the oocytes or embryos of women having CMV serum antibodies, it seems unlikely that CMV is transmissible from oocyte donation. Since only 27 cycles were performed in women with confirmed CMV antibodies, larger numbers will be studied to confirm this finding.