Red blood cell donor pregnancy history not linked to higher mortality in transfusion recipients

June 13, 2019

According to a press release from the National Institutes of Health (NIH), a new study has found that the sex or pregnancy history of red blood cell donors does not influence the risk of death among patients who receive their blood. The study adds to a growing body of literature examining whether blood donor characteristics such as sex, age, and pregnancy history affect the survival of transfused patients.

The research, which used three large donor-recipient databases for its analyses, was funded by the National Heart, Lung, and Blood Institute (NHLBI), part of NIH. The findings appeared online on June 11 in the Journal of the American Medical Association.

Previous studies have suggested that women with a history of pregnancy should be excluded from donating blood products such as plasma, the liquid portion of the blood, because it contains antibodies that pregnant women develop when exposed to fetal blood. The plasma of previously pregnant women has been linked to a potentially lethal complication called transfusion-related acute lung injury (TRALI).

The current study of red blood cell transfusions—not plasma—found no higher risk of death in recipients of red blood cells from once-pregnant women.

Scientists analyzed data from the NHLBI-supported Recipient Epidemiology and Donor Evaluation Study-III (REDS-III), a large, multicenter research program focused on ensuring healthy outcomes in donors and transfusion recipients, as well as the safety and availability of transfused blood products in the United States and abroad. Data from the Kaiser Permanente Northern California (KPNC) healthcare system and the Scandinavian Donations and Transfusions (SCANDAT) database from Sweden and Denmark were also used for the analyses. Together, the three cohorts made available data on more than 1 million patients who had received red blood cell transfusions from 2003 to 2016.

NIH has the full release with more information