Urticarial reactions in obstetric transfusion in Maiduguri, north east Nigeria.

A total of 135 obstetric patients who were first-time transfusion recipients at the University of Maiduguri Teaching Hospital were studied with respect to the incidence and clinical severity of urticarial transfusion reactions (UTR) in relation to the number of previous pregnancies. The overall incidence of UTR was 12.6%. Analysing the data with respect to the number of previous pregnancies the incidence of UTR were 0%, 0%, 3.8%, 8.3%, 21.7% and 37.5% among patients with 0.1, 2, 3.4 and 5 previous pregnancies respectively. However, all cases of UTR in the affected patients were clinically mild, manifesting with urticarial rashes and pruritus without any features of anaphylaxis. This data would suggest that the risk of UTR increases with the number of previous pregnancies. Therefore, multiparous patients need closer observation during transfusion therapy.