Red cell antibody screening in pregnancy: a preliminary insight?

Red cell alloimmunisation is defined as the development of antibodies in response to foreign red cell antigens through transfusion or pregnancy. In pregnant women even without the history of previous blood transfusion, this is possible through previous or current pregnancy with the presence of paternal red cell antigen inherited by the fetus. This study was aimed to determine the prevalence of red cell alloimmunisation among pregnant women without previous history of blood transfusion and the association with number of pregnancy and history of obstetric complications. This was a cross-sectional study in which 150 pregnant women were randomly selected from the antenatal clinic. Ten mls of peripheral blood was obtained for antibody screening using indirect antiglobulin test besides the routine antenatal screening. In this study, the majority (37.3%) of the women were primigravidae. Red cell alloantibodies were detected in two out of 150 (1.3%) patients which were subsequently identified as anti-C and anti-D. However none of the primigravida was alloimmunised. One woman of gravida 2 (2.9%) and gravida 3 (3.6%) each were positive for alloimmunisation. One of them also had a bad obstetric history. This study showed that the prevalence of red cell alloimmunisation among pregnant women was low in this centre. Nevertheless, red cell alloantibody screening test should be made available to reduce possible complications of alloimmunisation in mothers and fetuses