<p>Prevalence and specificity of clinically significant red cell alloantibodies in pregnant women - a study from a tertiary care hospital in Southeast Michigan</p>

Abstract

BackgroundMaternal red cell IgG antibodies can cross the placenta and cause hemolysis of fetal red cells in case of antigenic differences between maternal and fetal RBCs, leading to hemolytic disease of the fetus and newborn (HDFN). Although the incidence of anti-D associated HDFN has drastically reduced with Rh immune globulin prophylaxis, HDFN due to other maternal red cell alloantibodies still remains a concern. Prevalence and specificities of clinically significant red cell alloantibodies in pregnant females have rarely been reported in the USA.MethodsA retrospective chart review was conducted to determine the prevalence and specificity of clinically significant red cell alloantibodies in pregnant females who delivered at Beaumont Hospital Royal Oak between May 1, 2017 and December 31, 2017. A total of 4548 pregnant females were screened using electronic medical records. One female above 50 years age and two females with invalid ABO type were excluded from the study per IRB approved protocol. The remaining 4545 pregnant females with a valid ABO/RhD type and valid red cell antibody screen were included.ResultsOut of the 4545 included females, 440 had a positive red cell antibody screen. Of these 440 females, 34 had clinically significant alloantibodies, giving an overall prevalence of 0.74%. Anti-E was the most frequently identified significant alloantibody followed by anti-K. The most prevalent significant alloantibodies in RhD positive and RhD negative females were anti-E and anti-K, respectively. Significant association (p-value <0.001) was found between RhD type and the presence of clinically significant alloantibodies amongst females with positive antibody screen.ConclusionOur study aims to reiterate the importance of maternal red cell antibody screening during early pregnancy to help identify and manage high-risk pregnancies. Minimizing the exposure of childbearing age females to incompatible red cell antigens through unnecessary transfusions can help reduce the incidence of red cell alloimmunization and the risk of HDFN.

Alloimmunization to Rh Antigen (D, C, E, C, E) Among Pregnant Women Attending Antenatal Care in South Western Uganda

“…The alloimmunization prevalence is higher in this population when compared with developed countries such as the Netherlands, as reported by Koelewijn et al 15 (1.2%), and Sweden (0.5%), studied by Filbey et al 16 It is also found to be higher in comparison with other developing countries, such as a frequency value of 4.8% in Nigeria in the study by Jeremiah et al 10 The overall alloimmunization rate was also high compared with studies conducted in India by Mangwana et al 17 (1.3%) in New Delhi and by Dholakiya et al 18 (1.5%) in South India. The reduced rates of alloimmunization in developed countries could mainly be due to well-developed antenatal services and anti-D prophylaxis programs, [19][20][21] but in developing countries such as India and in African countries, there is a significant risk due to a lack of anti-D prophylaxis. 18,22 The variations may also be due to differences in race, environment, and the socioeconomic status of a given area.…”

A case report of minor blood group incompatibility (anti c) in a neonate - Is there a need for routine maternal antibody screening?

“…7 The prevalence of alloantibodies other than anti D antibodies among the pregnant women in developing countries varies from 0.3% in the United Kingdom to 0.72% in the USA. 8,9 But prevalence of the same among the pregnant women in developing countries is unknown. Many developed countries have universal screening programs for identifying alloantibodies among pregnant women.…”

Minor blood group incompatibility due to blood groups other than Rh(D) leading to hemolytic disease of fetus and newborn: a need for routine antibody screening during pregnancy

“…Many developed nations have implemented regular screening of all pregnant women and even have national screening programs (Table 2) (5,14,(16)(17)(18)(19)(20)(21). Although universal screening seems justified, the cost and infrastructure required would be immense.…”