A systematic review of red blood cell alloimmunization in pregnant women in Africa: time to do better

Abstract

Background and objectives: The presence of red blood cell (RBC) alloantibodies in pregnant women has been linked to the significant perinatal morbidity and mortality. A limited number of African studies have assessed alloimmunization to RBC antigens in pregnant women, but this literature has not been systematically reviewed. Thus, the aim of this study was to synthetize, by systematic review, the current evidence on RBC alloantibodies among pregnant women in Africa. Methods: We systematically searched MEDLINE, EMBASE and the Africa-Wide Information database to identify relevant studies in any language. Case reports, comments, letters, conference abstracts, editorials and review articles were excluded. Results: Of 269 potentially relevant articles, 12 studies representing 93 871 pregnant women fulfilled our selection criteria. Overall proportions of RBC alloimmunization exhibited a wide variation ranging from 1_1 (95% CI: 1_0, 1_2) to 12_1 (95% CI: 9_8, 14_7) per 100 pregnant women. Among clinically relevant antibodies, anti-D ranked as the most common, followed by anti-K and anti-E. Conclusion: The review of the available literature characterized the clinical challenge of RBC alloimmunization among pregnant women in Africa and revealed the insufficient volume and quality of research conducted in this topic. Improvement of quality of research should be a priority to gather stronger evidence that should drive policy decisions and strengthen practice in favor of RBC alloantibody screening in pregnant women as a standard of care throughout Africa