Based on a review of the literature, guidelines for the clinical use of cytomegalovirus (CMV) seronegative cellular blood products are presented. The clinical fields of application include obstetrics and foetal, neonatal, and transplantation medicine. Seronegative blood products are indicated for the transfusion of pregnant women, foetuses, and neonates until the 3rd month of life. They are also indicated in patients undergoing transplantation, if the donor and the recipient are both seronegative for CMV. This indication is extended to all transplanted patients with unknown CMV serology, and for all patients after lung transplantation. Finally, deleucocyted blood products are not equivalent to CMV seronegative blood products, but their use can be an acceptable alternative in the event of shortage of CMV seronegative blood products.