Importance Prior evidence suggests that plasma and platelet transfusions from female and
parous donors are associated with adverse clinical outcomes, which has led to the
predominant use of male donors for plasma and platelets in many countries. However,
studies on red blood cell transfusions have been conflicting. Objective To determine whether
blood donor sex and parity affect mortality of patients undergoing transfusion with red blood
cells. Design, Setting, and Participants This cohort study used nationwide blood bank and …