Antenatal blood typing and indirect antihuman globulin testing (IAT) should be performed routinely during pregnancy to manage the undesirable effects of hemolytic disease of the fetus and newborn (HDFN) that are associated with red blood cell (RBC) alloimmunization, according to findings from an institutional-based, cross-sectional study conducted in Ethiopia and recently published in the Journal of Blood Medicine.
When a pregnant woman’s immune system becomes sensitized to RBC antigens that are not familiar, maternal RBC alloimmunization is observed. This occurrence, in turn, can cause the production of alloantibodies, which can have a serious impact on the fetus and the newborn. In underdeveloped countries such as Ethiopia, a dearth of data are available on the scope of RBC alloimmunization.
Typing and screening are recommended among all pregnant patients, to evaluate alloantibodies and the presence of any unanticipated RBC antibodies, with the use of IAT. In fact, the detection of Rhesus (Rh) alloantibodies among RhD-negative pregnant women is critical to the prediction and treatment of HDFN in resource-limited counties.
The researchers of the current analysis sought to establish the extent of RBC alloimmunization among pregnant women who received antenatal care at Wolaita Sodo University Hospital, in Wolaita Sodo, Ethiopia, between Sept. 1 and Nov. 30, 2022.
Read more about HDFN symptoms and risks
A total of 422 pregnant women participated in the current analysis. Overall, 46% (194 of 422) of the participants were between 16 and 25 years of age. The participants were recruited via utilization of a systematic random sampling approach. Structured questionnaires were completed by all participants during face-to-face interviews, with data obtained with respect to sociodemographic features, obstetric history, and other clinical information.
All participants’ ABO and Rh blood types were determined using the test tube method. A, B, O and Rh blood types were established via the use of monoclonal immunoglobulin M (IgM) anti-D reagents.
Results of the study showed that the blood group distributions among the study participants were as follows:
- Blood type O: 41.9% (177 of 422) of the participants
- Blood type A: 29.4% (124 of 422) of the participants
- Blood type B: 18.0% (76 of 422) of the participants
- Blood type AB: 10.7% (45 of 422) of the participants
In all, 12.08% (51 of 422) of the women were RhD-negative. Among the RhD-negative individuals, 9.8% (5 of 51) of them were reported to have developed alloimmunization with RBC antigens and were thus considered to be IAT-positive.
A number of variables were linked to RBC alloimmunization among the pregnant women who were assessed in this study, including blood transfusions, postpartum hemorrhage, abortions/miscarriages, stillbirth, pregnancy complications, place of labor, and gestational age. A prior history of postpartum hemorrhage and miscarriage were both statistically significantly associated with RBC alloimmunization (P =.0001 for both).
“This study showed that [1] . . . of [10] pregnant women was alloimmunized,” the authors indicated. “Therefore, antenatal blood grouping and indirect antihuman globulin screening should be performed routinely to manage and minimize the undesirable outcomes of alloimmunization during pregnancy,” they explained. “It is important to look into additional population-specific antigens that may contribute to the significant amount of unidentified antibodies found in the current study,” they concluded.
